Undead Programming and You!

The only thing an Undead will do of its own volition is defend itself from an aggressor.
The spirit binding the corpse prefers to do nothing. The only higher priority is staying attached to the corpse, since unattached spirits are almost immediately dragged back into hell.
To prevent this they tend to strike first and fight with vicious desperation. The animating spirit would do anything to stay out of hell, and if that means sending your soul down in their place so much the better.

A Necromancer speaking with the Voice of the Dead can override this instinct and force the recalcitrant spirits into following simple orders. This is largely because the ghost knows that the Necromancer can quite easily shuck them from the corpse and reanimate with another spirit who will be more than grateful to leave eternal damnation.
Sadly for black magic enjoyers, the spirits animating the ungrateful Dead can't (or won't) understand complex orders. The swirling ectoplasms are endlessly spiteful and just kinda dumb. All personality and intelligence burned away by hellfire and pitchforks or, depending on your faith, broken by eternal solitary confinement in the metaphysical equivalent of a black room with padded walls.

Hence the classic Necromancer growls of "Attack this", "Move there", "Follow me" and of course "Go forth and kill all that live!". This removes the chance of things going wrong via an overcomplicated and/or a cunningly misinterpreted command, especially when you're in command of a horde.

Experienced Necromancers know that you can expand this exactly one step further with an "else".
"If I point, attack what I'm pointing at, else follow me." That sort of thing.
More complicated instructions are, alas, beyond the abilities of the Dead. GoTo's and Nested IF statements have historically run up against a hard barrier of confusion, stupidity, and the feigned incompetence of the Damned.

i have no idea what he just told me to do oh fuck oh fuck

What I Thought You Thought I Meant

When you first Raise or Subjugate the Dead to bring them under your control, you give them a simple if-then-else command.

For standard dungeon operations this is usually along the lines of "If I am attacked, kill my attacker, else follow" so they trail along and defend you if necessary.

The trouble comes when it's time for more complex orders or changing orders at speed. This could be due to a trap, player shenanigans, an ambush, plans failing to survive contact with the enemy, whatever.

Reprogram:

- You get one command per round. A second command takes an Action.
- A command can target an individual minion, all of a certain type of Dead (eg. all your zombies), or everything in earshot. 

So say you've been ambushed by some generic bandits.
You're a Necromancer with three skeletons, five zombies, and a giant undead crab. They're all still set to follow you unless you're attacked, but you want the minions to run in while your crab stays back to defend your squishy body.

You huff a Last Breath and have choices like -
- Command "All minions, attack my foes!" and start casting a spell, you can call the crab back with your free command next round once the spell has gone off.
- Use your free command to say, "All skeletons, attack their archers!" and use an Action for a second command, "All zombies, attack the sword guys!" You can't cast a spell this time, but at least you've got crab protection.
- Just say "Crab, attack anyone who gets close, else stay in front of me!" and start shooting over its shell. The rest of your Dead should shuffle in to attack if the baddies return fire, right?

Notice that you don't have to be that specific. "Attack the sword guys" is perfectly fine, and I'm not going to do some monkey's paw stuff with "harr harr technically you said attack the caster so now your skeletons are attacking YOU harr harr". The limitation is on micromanagement rather than how well you can word the command.

Note that if you've got prep time (like you've scouted the big bad boss in the next room and it hasn't seen you yet) you can easily spend a minute or two programming all your minions in advance so you don't have to waste time reordering them in the heat of battle.

we are experiencing a high volume of calls right now

Side note: The Voice of the Dead

Raising new Dead, subjugating existing Dead, or commanding Dead under your control requires one key component - the Voice of the Dead.

This is gained by breathing in the Last Breath of a sapient creature. Necromancers carry glass vials for this very reason, harvesting the Last Breath of a recently killed foe (or sacrifice) at the moment of death, then stoppering it to save it for later use.

A single vial is good for a few minutes of the Voice of the Dead, but makes you talk in a death metal growl that burns the throat. The Dead can't hear you otherwise.

This is, by the by, why vampires and liches and stuff make great Necromancers. They're always speaking with Voice of the Dead.

My table traditionally refers to a vial of Last Breath with extra blood and chunks as a "wetty"

Y tho

Micromanagement!

The Necromancer, among other things, can be a Minion Class. Raising an army of the damned is what players expect, and why wouldn't they?

My other Minion Classes are Halfling (one big minion), Goblin (1 minion/level) and Ratman (minions = level²).

The difference with the Necromancer is that there are no hard limits. Necromancers don't have an upper bound beyond "how many can I raise at once?" and "how many can I keep alive?" and "how many can I reasonably fit on the marching order sheet?".

My intention here is to make the difference one of control.

You can have an arbitrarily large horde, but actually managing them in a combat situation is hard.
You don't have fine-grained control unless you're willing to spend all your time yelling orders from the back rather than casting spells (which is perfectly valid Necromancer behaviour, I may add - also true of sports coaches).

This isn't a real issue if you only keep a few minions at a time, since you can order individual minions to do different stuff as the need arises.
Problems start to occur when you're bringing in a horde of the Dead and can't do much more than a Necromantic select-all.

Of course having a horde of zombies with you will also have noise implications on the Underclock, but this command/reprogram thing is more about adding a bit of friction in combat or otherwise under time pressure.

real heads know

Implications

This works great if you've got an army of the Dead. Just set and forget! "Kill everyone in the village", "prevent anyone from entering the graveyard" or whatever, no questions asked.

Plus they'll keep doing it forever unless you go over and change their orders yourself. No big deal if you forget to do that, you're leaving your mark on the world!

It also explains why armies of the Undead tend to have a fair few living Necromancers in there. 

If you're the head honcho you could technically do it all yourself and just send all your dead into battle, but it means your enemies can fairly trivially kite your troops, hide behind shield walls and barricades, or bait them into pit traps. Having Necromancer lieutenants around to micromanage individual units gives you way more tactical flexibility when the Living try that nonsense.

This happens to be why tomb guardians often only seem to come to life once you've claimed the ancient treasure. Some Necromancer once commanded, "if someone touches the amulet, kill them! Else pretend to be a pile of bones" and never came back.

It's often why senior Necromancers like to have a particular room where they hang out in the dungeon.
It's the only place where their orders are juuuust right. It would be really annoying to reset the commands on all the arachnoid bone-constructs lurking above the throne room who have been ordered to drop down when they hear the words "Now, my pretties!!"

Go forth and kill all that live!