I’m always careful with how much I use the undead in my campaigns. Don’t get me wrong, I love using them. But I believe that things like the undead should be used in such a way that it enhances the creep and/or terror factor of your campaign. Just dumping a bunch of skeletons or zombies into an encounter as throw-away bags of XP undermines how chilling it would really be to encounter something dead now walking around again. Nevermind several somethings.
I also feel that the undead are most effective when their exact origin and method of elimination are a bit of a mystery. In my D&D campaigns so far, reducing incorporeal undead to 0-hp causes them to fade away for anywhere from one to four days (d4 roll); corporeal undead can take a bit longer to pull themselves together, re-manifesting in one to eight days (d8 roll). But unless the characters can discover what is causing the undead to manifest in the first place and somehow deal with that, those particular undead are going to keep coming back.
In my current 5e homebrew campaign, I wanted a way to demonstrate that the land was still tainted by a magical cataclysm several hundred years previous. I used aberrations to partially demonstrate this; all aberrations in my campaign were born from that magical cataclysm, not existing before that point. But I wanted a way to show the land was still poisoned by this past event. So I came up with a type of undead to fit that theme. Many undead manifest from some horrible traumatic event while they still lived, or are created at the whim of a necromancer. Coffin Knockers are created purely by an accident of interment in a magically-tainted location.
Medium undead, chaotic neutral
Armor Class 13
Hit Points 16 (2d8 + 6)
Speed 30 ft.
STR 13 (+1) DEX 8 (-1) CON 16 (+3) INT 8 (-1) WIS 10 (0) CHA 5 (-3)
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities poison, necrotic
Condition Immunities charmed, grappled, paralyzed, petrified, poisoned, restrained
Senses Darkvision 60 ft., Passive Perception 10
Languages understands the languages it knew in life but can’t speak
Challenge 2 (450 XP)
Partially Incorporeal The coffin knocker can move through an object or objects, but not another creature. It may choose to end its movement inside another object.
Rejuvenation If the coffin knocker is destroyed, it regains all its hit points in 1-4 (d4) days unless its remains are sprinkled with holy water and re-interred in untainted ground. Alternatively, if the tainted ground is somehow cleansed the coffin knocker will fail to rejuvenate.
Slam Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6+1) bludgeoning damage
Tainted Mana Bolt Ranged Spell Attack: +1 to hit, range 30 ft., one target. Hit: 10 (3d6) necrotic damage
Coffin knockers appear much as they did when they were interred, though parts of their form can be seen to become incorporeal seemingly at random. While not possessing all the intelligence they did in life, coffin knockers are still more cunning than purely mindless undead, and are often able to act much as they did in life.
I envision coffin knockers causing some terror in small villages in my world, as deceased friends come back for a visit simply because they were buried in a patch of magically-infected ground. Inhabitants would learn over time which spots were safe for burial and which weren’t, but that wouldn’t stop Aunt Edna from coming back every few days, until someone could deal with her permanently.
What sorts of special undead do you use in your campaign? Share them in the comments section.