Saturday, 28 April 2018

Putting Your World to Death

I hope, for your sake, that your world has a good long life ahead of it.
But if you've suddenly found yourself dealing with imminent apocalypse, hopefully this will help you set up the fall.


A note for my players: Possible spoilers ahead. I don't think there's anything suuuper major in here that will ruin stuff, but read at your discretion.



The Impersonal Apocalypse

First things first - some context.

Mine is an impersonal apocalypse. Shub-Niggurath is a huge but non-sentient creature that is breaking out of the world. It will shatter the world like an egg. It doesn't think. It does not, and cannot, care about this.
Similar might be the sun going out, or a meteor coming to destroy the Earth or Cthulhu rising. Nobody caused this. It's nobody's fault. It just is. And now we've got to deal with it.

This as opposed to an apocalypse caused by something with an actual will and sentience, like Sauron or Thanos or a generic Ancient Evil That Has Awoken. There's always the slim possibility that you can reason with or trick such an entity. At the very least you can murder them or seal them away or whatever.

This doesn't change the following post all that much, but it's maybe useful for context? Anyway.




Faction Endgames

Your first task is to work out what your campaign's main factions are going to do now. How do the existing factions react? Are there any new factions brought forth by impending doom?
It's the end of the world. The world ending is bad for everyone. Who's trying to stop it and how are the planning to do it?
And most importantly - how do these plans oppose and clash against each other?

I've got three general spheres for how factions are reacting to the rise of Shub-Niggurath:
- Save humanity at all costs.
- Save the planet at all costs.
- Save the universe at all costs.

Examples:
The Apocalypse Dragons are here to save the universe. They live and act on timescales so vast that the spread of a planet-cancer across the universe over aeons is a real and present threat. They will destroy the world and all life on it if it stops Shub-Niggurath from spreading.

The Necromantic Duvan'Ku are here to save the planet. They're willing to sacrifice as much of humanity is necessary to ensure the planet's survival. After all, it's not like they'll kill off the trees. In a worst case scenario "living" as Undead even after everyone else is dead and gone.

The sin-eating Demons, perhaps counterintuitively, want to save humanity. They feed on sin, and if there are no sinners left then they'll starve. If they found a way to save humanity at the expense of the planet and the wider univere, they'd do it.


The key to all this is that every faction has good reasons for doing what they're doing. They're generally all doing what they think is right and for the greater good, but also with a level of self-interest that can clash against some factions and align them with others.
Their reasons and motivations might be different, and there's a lot of conflict depending on what time scale they're working on and what they personally value, but each faction thinks they're the good guys willing to do what it takes to save what's important to them.

There's an extra layer for my game because I've got players who've been in the same campaign world for literal years. These factions are known.
They've got all sorts of friends and enemies in the world. There are even recurring characters wandering around who some players recognise from previous adventures with previous characters. It's intense! The joys of a long-running game!
Now suddenly all the factions have shifted to their final endgames and it's really kicked the game into a higher gear. With that game history on their side, the players have enough of a grasp of the game world to really work out how they'll make an impact.





A Note on Agency in a Dying World

Players have a lot of agency in a world that's fairly fucked up.
I think it's because you can really see the cracks. Who do you help? Who do you oppose? Who do you exploit for personal gain?

As Zak says in this long ago post, a sandbox game needs roguish, pragmatic, self-motivated characters to work properly. There's a lot of stuff for characters get roguish and pragmatic about when everything's falling apart.

And when every faction is doing bad things for the right reasons, it gives a lot of solid reasons for players to support, oppose or unite various forces. It's pretty cool!



Apocalypse Timeline

This is your second task.
Decide how long the world has to live. For me, I gave them just over a year.
Shub-Niggurath began rising in November last year, it's going to crack the planet in December this game-year.

Now it's time for the fun part - make a calendar of what each faction is doing each month!
You'll be updating this timeline as and when players mess with the course of events.

Since we're past this point in the timeline now, I suppose I can show you at least this much.

Players may not want to expand

The idea with this is to make sure you know what the big movers and shakers are doing, especially in the case of players just jumping up and heading off somewhere new. Gives you something to work around!
It also means that when players do something of real significance, you can work out how they rebounds and impacts different forces in the world.
My intention is to release each of the things by the end of the month, but I'm a little loosey-goosey on the exact timings. Preferably the players are on the surface to witness such things when they happen so I miiight nudge the dates along a little bit to make it a bit more cinematic.

Deep Carbon Observatory has a similar sort of long-range timeline thing that happens if PCs never influence events, so this is definitely in that vein.


I really wanted to use apocalyptic events from Revelation to get that good fucked up apocalypse feel. Evangelion influence again, probably.
Seven Trumpets, Seven Vials, all that good stuff. Combine with all the other various swirling ideas and themes, shake, and strain over ice.
So far it's all lined up weirdly nicely. When the First Trumpet was due to sound I looked around to see what could have kicked that off, and conveniently one of the players had managed to set the table for me!
They gave the alchemist who wanted to create a Shub-Niggurath-destroying omnipoison a sample of extremely powerful demon spider poison. The alchemist tried it out, it went wrong, and now there's no grass and cancerous tentacles and a third of all flora has withered and died. How prohetic!

I don't care I loooooove big fuckoff indestructible natural disaster dragons

End Times Encounters

The third task is adjusting your encounter tables for this new reality.

One thing I'd say - don't weight the results via multiple dice in the apocalypse. 
I've moved all my end times encounter tables from 2d6 to a straight 1d12 so all results are equally common.

Having a weighted 2d6 is for conservative simulation of a fairly dependable ordered world. Common local encounters go in the middle numbers, doom-wizards and elemental dragons go on the rare numbers. Having a straight 1d12 roll means you see the doom-wizard as often as you see anything else, which works for the chaotic terror of the apocalypse!

The other thing I've done with a number of Lair results is to put them in conflict with "Roll Again", so there's going to be much more naturally occurring conflict in the overworld. It's the apocalypse, everyone's fighting everyone else, dark times for all really!
Seeing two sides in battle is perfect for a Lair result. The encounter is close and the players can easily engage if they want, but they can also go the other way and avoid the situation.



Information and Agency

Players need information to make informed choices.
Making informed choices is Agency.

I've been honest with players about when the world is set to end, ie. December 1601.

I figure we've all played enough games where the apocalypse is juuuuuuuuust about to happen, but you've got plenty of time to run around doing some final side quests before actually triggering the final mission.
(Looking at you, Mass Effect)

By giving a set end date I'm saying that I'm legit about letting the world die. GOOD LUCK!

There's already a sense that they're going to have to be reeaally careful about using time-advancing mechanics like Carousing or Spell Research. I'd previously made those things take a while simply so that the game timeline advanced sorta kinda at a pace with real time. 
Suddenly downtime is recontextualised from a straight money sink to a real risk/reward mechanic.
Do we risk spending a week or so partying to level up? What if something terrible happens in the mean time?

I've been stocking up the Rumours table with more news than before. I've de-emphasised hints at nearby dungeons. The players know which dungeons are important now. Instead the rumours tend to be about wider events in the world, and hints at the sort of threats that are becoming more prevalent in the overworld.
Rumours about what's happening on the front lines against the Dead, updates on the movements of Battlefortress Fate, etc etc.
Gameplay is necessarily moving up to a grander scale, so the rumours reflect that. Nobody cares so much about Granny Questgiver's lost cat when there are literal angels falling from the sky.

Be liberal with the information you give out. Nobody's cagey in the end of days! Everyone anyone meets is going to have some story about something major happening somewhere, so let it happen!


In Closing

The end of the world is an exciting time. Embrace it!
I like to think my game has always had high stakes, but that's often been in the context of character life and limb. Suddenly world-saving stakes have shifted my game to another gear!

No matter what the outcome, I imagine the aftermath of the apocalypse is going to gear-shift my game again.

Hexcrawling and rebuilding a shattered world? Space voyagers flying off on shattered fragment of Earth? Time-fucking attempts to rewind and rewrite history?
I'm excited! And if your world is ending, you should be too!

Wednesday, 7 March 2018

House Rules Update! 2018 edition

Another year, another metamorphosis!


PDF here


The main impetus this time around is basically to trim off as much fat and fiddly bits as possible, especially in the combat rules. If there's something in the rules that never gets used or I always forget about, it's gone.
It's become increasingly obvious that the Gambit is the only combat option anyone really needs. It's simple, has an obvious risk-reward angle, and has the exciting partial success possibility.
I've trimmed off anything that's not covered by a Gambit and simplified the rest.

The other thing is that Sneak Attack has always been a sticking point in the game. It's a weird outlier in terms of how skills work and is useless without a high Stealth to back it up.
Probably the biggest change in this update is reworking Sneak Attack and Stealth so they're not so tightly linked. Sneak Attack has been reworked into Backstab which is primarily for ganging up on the same enemy, but also still effective for traditional shanks from the shadows.
I'll go into it more when I get to that section below.

On the less rules-tweak side of things, I've added a few more bits to make the rules a bit more standalone, like putting basics about HP and AC and stats in the doc. It's not exactly a Ten Foot Polemic standalone game (yet?), but it's in here so you don't have to cross-reference with the LotFP rulebook so much. This is important if you are, for instance, one of my own players trying to use my rules to run your own session.

I've pulled out the relevant sections of the rules for ease of use, but do feel free to follow along in the house rules document.
So here we go, a change log with explanations and stuff as we go.



Char Gen

- Removed Ammo Dice
Ammunition isn't tracked unless something happens to make ammo tracking important.


I'll talk about this here - the death of the Ammo Die.
Oh wow the site I originally got it from seems to be dead! My house rules are old!
Archive copy of the ammo die post here.
Anyway, the idea behind the cascading Ammo Die made its way into the Black Hack as the Usage Die. Seemed like a great way to track arrows etc in the abstract, but man I can't remember the last time someone fired enough arrows for it to matter. When the bulk of the game is dungeons and firing into melee is dangerous, you just don't fire that many arrows.
I've left the door open for resource management if people are in the middle of a desert or something, but in the main we're not going to be tracking ammo any more.


The Basic Basics

- Added this whole section


 Just making things a bit more clear because there are some minor changes from LotFP.
Most notably, making it clear that HP is your luck-shield not your life points per se.
Also, Surprised AC in the LotFP rulebook is surprisingly hard to find, so that's here now.
Armour rules also gathered into one place, which means there's a teaser for the new sword rules in here too.

Stats

- Added this whole section



Explanation of stats because it's subtly different from LotFP, mostly by accident over time.
Clearly the lore/reasoning is more or less transposed directly from the LotFP rulebook.
Most importantly - something I never realised was that Int/Wis were supposed to influence the Saves of people targeted by Magic-User/Cleric spells! I've never done that, so it's gone. In its place is being a better caster via recovered from Interrupted Casting and Spell Swaps. Works for me.
Oh and did you know that Charisma doesn't affect Reaction Rolls by the LotFP rules? I sure didn't! So that's called out as affecting Reaction Rolls now.




Hazards

- Moved Falling here
- Added Fire rules for ease of reference
- Added Drowning


Original falling rules make falls very dangerous, and means anything that makes your fall count as 10' less could potentially save you from massive amounts of damage.
Fire rules in LotFP are nice. I like them, but added a few extra bits from rulings we've had in the past.
Drowning has claimed the life of several adventurers in my game, would you believe. The ruling at the time turned out to be surprisingly functional - 5 rounds of activity (+/- Con) before you start taking damage.


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Rations

- Added temporary shelter ruling


All the same as before, except that it's possible to set up a makeshift shelter in the wilderness if you spend a day and roll Bushcraft.
Requiring a tent and rations to heal quickly in the wilderness works well, but what do you do if you forgot to buy a tent and/or your tent got destroyed by an angry bear?
You can build a semi-permanent shelter in the wilderness with a day and a successful Bushcraft roll.
Tents are a shortcut that you can pack up and move easily every day, so they're much better for travel than spending a day scratch-building a shelter every time someone needs to heal quickly.


Magical Healing

- Tweaks to Cleric spells that deal with poison


This has been in the poison rules post for a couple years now, but this is the first time I've stuck it in the house rules doc.
Delay Poison means you'll likely have processed the poison before it kills you.
Neutralise Poison... neutralises poison.


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Basic Combat

- Added Magic to this section


This is in the Classes section too, but it really should have been here all along.
Declare casting at the start of the round, you need to be protected until it goes off at the end of the round. Standard in my game since forever.


Fancy Combat Options

- Removed Bumrush
- Removed gimmicky Parry rules, rolled Disengage into Parry
- Replaced Sneak Attack with Backstab
- Added Evade
- Clarified Wrestling
- Moved setting spears to Reach weapon section




Here we go! Some big changes.

Bumrush/Charge is easily a gambit. I'm surprised it lasted so long really.
Parry and Disengage were two similarly defensive but separate actions before. Now Parry is just the overall defensive "please don't hurt me" action, boosting AC and avoiding Opportunity Attacks.

The new Backstab will come up lots more. It's primarily a bonus for flanking enemies now, with a secondary use for killing surprised enemies. Flanking is a 5e-style thing, multiple people attacking one target in melee. Optimally you'll have a tank distracting the enemy while you come in with the Backstab. Conveniently this can be used to make pack-hunting enemies more dangerous by giving them good Backstab scores.

Evade appeared in this skills post as "Combat Stealth" but it's in the house rules now. Takes an action and a successful skill roll, so only useful if you have reliable Stealth.
Great for setting up a Backstab since it gives you +4 to hit and they can't target you on their next turn, guaranteeing Flanking.

Together, Aim, Evade and Parry form a sort of combat boost trifecta.
Aim is use an action, boost ranged attack.
Evade is use an action, boost melee attack.
Parry is use an action, boost AC.
Maybe the almighty Gambit will eat them all next time round, but I like the balance for now.

Wrestling is great. Adding some clarity for multiple wrestlers, and how wrestling rolls happen on both sides of the round.
+/- 1000 for natural 1s and 20s is for the silliness of it, but also neatly describes "a natural 20 automatically wins a wrestle, unless both people roll a natural 20 in which case it's still down to modifiers".

Spears in a bit.

Melee Weapon Types

- Choppy weapons changed: deal improved damage die against light armour or less
- Stabby weapons changed: +1 to melee AC and +1 to melee attack bonus



I still enjoy differentiating the weapons like this, even if it bumps up the complexity a little. With a general lack of magical weapons in a low magic game, weapon choice takes up some of the slack.
They used to trigger effects depending on whether you rolled evens or won initiative or whatever, but that's really too fiddly and complicated. It might maybe be fine if you're a player, but for poor old me rolling for a bunch of enemies at once that's too much overhead.

So now this should all be much easier for someone rolling a bunch of dice at once, and hopefully easier for the players.

Choppy axes deal improved die of damage against low armour targets. This means a greataxe vs a generic peasant rolls 1d12!
Smashy hammers are the same as before, piercing high armour targets.
Stabby swords are a straightforward upgrade against any target. +1 to hit, +1 to melee AC. Pair with a shield and you've got +2 AC against both melee and ranged attacks. Heavy armour, sword, and shield gives you a tip top 20 AC which is the effective maximum.
I might rename "Stabby" to "Versatile" to make it clear that they're good for offense and defence, but I'm keeping it for now.
Shanky is unchanged, deal bonus damage in a Wrestle if your roll beats their AC. Knife fights get messy.
Whippy is also unchanged. Ranged wrestle.

Noted here too: the Fighter gets extra bonuses on top of these. They're better than anyone else with any weapon, which is as it should be I think.


Melee Weapon Options

- Reach Weapons allow you to make an Opportunity Attack against enemies moving into melee.


Not actually a change, just not highlighted like this before. Was previously under the overcomplicated Parry action.
Opportunity Attack against approaching enemies makes the spear a superior defensive weapon, and good for defending your friends.

Also interacts with the new disengaging Parry. You can close in on a spear wielder by using Parry to avoid the Opportunity Attack, at the expense of not being able to attack them when you get in close enough.
Dropping Charge/Bumrush means that I can just drop setting spears against a charge. Spears are set against anything moving into range automatically, but no bonus to damage.



Ranged Weapon Options

- Firearms are all counted as flintlocks now.
- Rifled barrel improves Aim, instead of making up for range penalties
- Firearms ignore all armour at close range (all ranges for musket)


In a game where all of the various weapons have been cut down to several damage categories, it's a wonder I stuck with the Matchlock/Wheellock/Flintlock thing for so long. Who cares?
Everything is now counted as a flintlock, and if you want to have a rad wheellock on your pistol I'm not going to penalise you for it.

Range penalties literally never come up. I'm not going to measure ranges, and most if not all combat in this game is at short enough range that you don't need to worry about it.
Getting a rifled barrel means you double the Aim bonus to a big +8, at the expense of doubled reload time on a firearm you'd never manage to use more than once a fight anyway.
Finally, a reason to buy an Arquebus over a Pistol.
This should be an improvement even if you do measure ranges, since the Aim bonus makes up for the range penalties. Get your snipe on.
I was also doing the by-the-book firearms thing where guns pierce 5 points of AC, but piercing all armour is easier to adjudicate even if it's not entirely realistic.



Death and Dismemberment

- Updated for the modern era




This is all in pamphlet form now. Go see that post for an explanation of my game's most fiddly subsystem.
The main thing is to call them "Death Tokens" instead of "Death Dice", and add a bit more clarity. I think it's fine now.
This is a big wodge of complexity in the middle of an otherwise fairly rules light game, but it leads to a lot of fun gameplay for me. I swear.


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Wear and Tear

- Removed weapon/armour Quality
- Removed sacrificing armour to reduce damage
- Added England Upturn'd misfire table for Notched firearms
- Dwarfs can completely fix a single item per day, up from one Notch per day.



Having different weapon Qualities which gave different chances of taking Notches was a good idea in theory but definitely very easy to forget about in the heat of battle.
You know what's not easy to forget in the heat of battle? Crits and fumbles! Any time a natural 1 or 20 comes up, people notice. So now weapon/armour damage is triggered by those exclusively.

Part of the impetus was having high quality weapons and armour to replace magic weapons and armour, but that was a nice idea that never worked out great. Just make it extra fancy or something. Hell, make it unbreakable. That's as good as magic.

There was a rule here last time where you could sacrifice armour to reduce an attack's damage to 1, but that's gone now. I kept forgetting and so did the players.

England Upturn'd has cool a firearm-exclusive misfire table that it wold be a shame not to use, so I'm using it.

Dwarf repairs are better now, just because it makes it easier. Give a Dwarf a day and he can fix an item. Solid. A Mending spell always fixed an item completely, but I'm calling it out here to make it clear.



Skills

- Called out skill-boosting equipment and skills that get boosted by Intelligence
- Backstab is a reworked Sneak Attack
- First Aid reworked - forces patient to Tempt Fate on a 6 instead of dealing damage, no longer heals HP
- Added Rapid Reload to Sleight of Hand
- Added Evade to Stealth
- Added Invention to Tinkering



A few changes around here.
Intelligence modifies Arcana and Languages. Nothing new there.
Specialist's Tools give a +1 to Tinkering and First Aid, that's not been in these rules before.
Same with Crampons granting a +1 to Climbing, which needs calling out really.

Backstab is a big change. See Fancy Combat Options above. Upgrade hits against surprised or flanked enemies to crits.

First Aid is now focused directly on field medicine, healing up a person who's reached 0HP and is dying from Death Tokens. The combat medic skill to bring the dying back from the brink!
Failing on a 6 used to deal 1 damage to the patient, but now it makes the patient Tempt Fate which fits the Death Token angle better.
Healing HP with First Aid has been scrapped, eating to heal works better and more reliably.

Rapid Reload skill was sort of in the rules before, but it's here now.
Roll Sleight of Hand to get a free Reload action. This means you can Reload twice in one round, or even Reload while fighting. Potentially fire a gun every 3 rounds if you've got good Sleight of Hand and focus on reloading, which almost makes it worth it.

Evade, again, see Fancy Combat Options above. Dodge and weave to gain an advantage against an enemy.

Invention has been in the game for a while, because players looove coming up with bullshit mechanical things like breathing apparatus or complicated traps.
Only change is that if a device works successfully it gets a +1 to Invention rolls in future, so you slowly build it up until it works consistently. Previously this had it working after three successful uses, but I think this is mechanically neater.

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Rune Magic

- Minor tweaks


Due to mystery campaign reasons (and mild balance woes) the Repel rune doesn't generate stuff any more, only pushes it away. Breath weapons are too easy I guess!
There are a few other bits, but that's the main one.


Classes

- Added everything for each class, not just the things that are tweaked from baseline LotFP. You can run a class out of this document now.


Just makes it easier for people who aren't running LotFP to figure out everything a class has.

Onto actual changes that matter.


The Fighter

- Added Weapon Mastery


Fighters are simple. This is mostly on purpose, it's a straightforward class with a straightforward focus on straightforward murder.
People who want to be a fighter type tend to roll Barbarian nowadays. But I have a condition where any time we haven't had a Fighter in a while, I want to make Fighters better.

So here we are. Weapon Mastery. As seen in the Melee Weapon Types section, different kinds of weapons get different kinds of bonuses.
Fighters get those and more, with the bonuses intended to synergise with the base perks.
Having a Fighter that carries one of each weapon around sounds great.

The Choppy upgrade is suspiciously similar to 5e's great weapon thing, from which I took it.
The Smashy upgrade replaces the old "shiver armour on evens" thing. Hammer attack to make the enemy easier for your allies to hit. Combo with the new Backstab to good effect.
The Stabby upgrade means swords are very much the defensive weapon - use an action to Parry and hopefully you'll trigger one or more counterattacks. Amazing for a fully armoured and shielded Fighter.
The Shanky upgrade makes Fighters even more brutal wrestlers, seeing as their attack bonus means they'll win wrestles a lot.
The Whippy upgrade is to do some Indiana Jones shit and trip people up.



The Magic-User

- Altered Spell Interruption to make Chaos Mages more possible
- Made Spell Swap more lenient


Spell Interruption used to mean you could prevent a Spell Collapse with a Save vs Chaos.
Now a Save vs Chaos means you get to see what the Spell Collapse will do first, then choose whether you negate it. A small but significant change.
Shout out again to Aura Twilight's chaos magic table which I can't link enough.

Spell Swap now only has a penalty if you're swapping a higher level spell to a lower one, due to the potential magical leakage. You're forcing a larger amount of energy into a less complex spell and the magic might start leaking in around the sides.
Previously you had a penalty equal to the sum of the spell levels, so this is more lenient.
I want it to be slightly risky to swap a spell, but not so risky that I hear people going "nonono!" to a spell swap like the wizard's about to cast a Summon spell.

These Spell Swap rules carry over to other casters.


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The Extras

- Added this class


My Extras class is so similar to Manola's original Extras class that it's not worth a class blog post.
The only minor difference is that the "Magic for the Masses" rule applies to all items.
If you've got less than 10 of an item, it can be used once per scene and each takes up a separate Encumbrance slot.
If you've got 10 of an item, it can be used every round and all 10 items take up a single Encumbrance slot.

Two bows means you can fire arrows twice per scene.
Ten bows means you can fire arrows every round.

Two suits of chain armour means you can get Chain AC twice a scene.
Ten suits of chain armour means you have Chain AC at all times.

It's very strange and meta, but that's the Extras in a nutshell!



The Inheritor

- Added this class


Recently detailed in the Inheritor class post.
Eat monsters to steal their abilities and use them against your foes.
Enough of a niche that it doesn't step on other class's toes, and the game's first Inheritor so far has ended up being really interesting!


So that's that. A whole lot of incremental changes that I hopefully won't have a need to fiddle with for a while. Enjoy!

Friday, 23 February 2018

The Inheritor, or the Extremely Omnivorous Blue Mage

The Inheritor is based heavily on Courtney's Blue Mage except with the vore stuff cranked up to maximum.
In essence - eat monsters to steal their abilities.

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To die beneath the harsh eldritch light of the Black Sun is to be born anew. Soul scourged, memories scattered, barely in control of this new body of black-veined mud.
The life of a newly formed demon is one of sin-eating, slow-gained sentience, and hard-won metamorphosis. A new body with an old soul, emerging into the darkness of the end of days.

But this is not you.

You are an aberration amongst even your own aberrant kind. You crawled from the viscous mud of the river Lethe fully-formed, already settling into shape. Stranger still, a weird grasp of your own twisted flesh allows you to alter your body further. A malleable self-image that can be restructured to assimilate the organs and energies of foes you confront and devour.
You are no mere demon. You are something more.

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The Inheritor


Core: 1d6 Hit Die. Minimum 3 HP at first level. Saves and Exp Track of the Magic-User.
Monstrovore: The Inheritor is a strange type of demon that can devour monsters to gain their powers.
A sort of monstrous and extremely omnivorous Blue Mage.
Mutable: In order to absorb a power or ability, the Inheritor must have been affected by that power or ability. Then they must eat whatever part of the creature gave them that ability, like a ghoul’s claws for paralysis or spider’s fangs for their poison bite.
That is, to steal a powerful attack you must survive that powerful attack. Then eat them.
In the case of passive abilities, like a Spider’s climbing or a Fire Beetle’s glow, you can steal the ability as long as you’ve witnessed it in action.
During the absorption process the Inheritor collapses into a pile of randomly mutating flesh and mud and strange organs. This process takes 10 minutes.
You can take multiple abilities from the same creature if you wish, but each individual ability is a separate Mutation.
Inheritance: Each ability the Inheritor has stolen is called a Mutation. Each Mutation grants the Inheritor a minor passive ability based on the Mutation. Taking a Giant Spider’s climbing ability might give a passive +1 to Climbing, taking a Gelatinous Cube’s paralyzing touch might grant soporific saliva.
The Inheritor’s Mutation Capacity is equal to their level, eg. a level 3 Inheritor has 3 slots for Mutations.
The Inheritor’s maximum MP is double their level. They regain all lost MP after 6 hours sleep.
Full Power: Spending a Meat Point (MP) allows the Inheritor to use a Mutation at full power for a round, using it as the original creature used it. This causes their flesh to bubble and unfold into a monstrous parody of the original creature as they unleash the stored power.
Other than available MP, there is no limit to the number of powers that can be activated simultaneously.
Doppelganger: The Inheritor can entirely consume a person to gain their voice and appearance. Each whole disguise  counts as 1 Mutation. It costs 1 MP and 10 minutes to transform, but the transformation is permanent until you transform back.
You also get a vague taste of their memories - ask the DM three questions and he must reply truthfully if they’d have known the answer.



"I'm spending a Meat Point to run as fast as a dog!"


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Core:
The base of this class is a Magic-User with a bumped up Hit Die.

Monstrovore: 
You get it. Eat monsters, gain their abilities.

Mutable:
The idea of a PC going around collecting monster abilities is a little bit scary for me because my game has lots of weirdo monsters with weirdo powers. What if they pick up some completely overpowered ability and break my game?!?

There are three main risk/reward aspects to collecting monster abilities:
  1. You have to survive a powerful offensive ability in order to obtain it. If you want that dragon's breath weapon, you have to survive the dragon's breath weapon.
  2. You have kill and eat the powerful monster. If you want that dragon's breath weapon you're going to have to actually slay the dragon which is no mean feat.
  3. It takes a 10 minute Turn to assimilate monster abilities, so you need to be protected until you've fully absorbed the creature's ability.
This means that if the Inheritor picks up a powerful ability, they've earned it.
It's already getting a little Pokemon with swapping out moves for more powerful moves over time, but I'm more than ok with that!

To be clear - you can steal multiple abilities at once from the same creature. So if you eat a spider you could steal its Venomous Bite and its Spider Climb.
Bear in mind that each distinct ability takes up its own slot.

Inheritance: 
This is obviously the main gimmick. Steal an ability and you get a passive perk which is always on.

As an example, at time of writing the Inheritor in my game is at level 4.
She's filled her 4 Mutation Slots with the following abilities and associated passives:
  1. Fire Beetle glow (Glow faintly in darkness)
  2. Dwarf darkvision (Low light vision)
  3. Giant Spider venomous bite (Paralysing bite)
  4. Gelatinous Cube transparency (+1 Stealth due to mild translucency)
Each of these passives has made her a little more mutated. The fire beetle glow comes from softly glowing orbs under the skin, the cube's translucency has made her a little more squat and slimy.

Full Power:
The resource management part of the class. You get two Meat Points per day per level that you use to amplify a stolen ability back to full power!
Spending a Meat Point instantaneously gives you access to the full active version of the ability for the rest of the round.

For this Inheritor, spending a Meat Point will stoke that faint glow to full lantern-strength light, or she can activate full power Gelatinous Cube transparency to go practically invisible.
Of course the big ticket item here is the Giant Spider's poisonous bite - spend a Meat Point and you can bite with a spider's devastating 1d6 damage bite and Save vs Doom poison.
She did well to acquire that one.

A single Meat Point will keep an ability at full power for only a single round, so some abilities are more useful as a passive than an active ability.
Bumping Fire Beetle glow up to full torchlight lasts for a full round, but one round of lantern-strength light is not so good for exploration over the course of ten minute Turns.
Cleverly this Inheritor has exploited the passives to create a better combined effect, something I hadn't initially expected. 
You may notice that the combination of Fire Beetle soft glow and Dwarf low light vision will combine to result in constant passive darkvision. I thought that was real neat! Good use of player skill and exploiting edge cases, so it's perfect.

Doppelganger:
Straight out of Prototype, eat a person to become a perfect clone of them.
This is ripe for shenanigans, and also means that an Inheritor who is willing to use up a Mutation Slot on a normal person disguise can avoid looking like a weird horror-chimera if they want.

The first use of this ability was pretty fucking wacky - the player ate the corpse of their previous character in order to transform into her.
The ability got swapped out for another power fairly quickly, but it was creepy while it lasted. Especially for the other characters who had buried her.