D&D: Five Enemies That Just Won’t Die No Matter How Many Times Slay Them

One of the new wrinkles in 5.5E are monsters that don’t die when you kill them. These five monsters take more than hitting 0 hp to slay.
D&D in the 5.X era is usually pretty straightforward. You go around fighting monsters and looting treasure in between bouts of running an inn and shopping with a carousel of beloved NPCs and weird little guys you find along the way. Presumably, at some point, the Bard seduces someone.
But in 5.5E, WotC has complicated the formula slightly. Some monsters don’t die when you kill them. Or at least they don’t stay dead. Sure, you can drop them to 0 hit points – but rules as written, some monsters take more than just killing them to get rid of them permanently. Here are five to watch out for.
Arch Hag
Arch Hags are one of the new high-CR monsters in town. And they are nasty. Not only will they curse you with their various attacks and counterspells, making it harder for you to deal with them in the first place, but they’ll also keep coming back.
Killing an arch hag is no mean feat. Most of the time, when you drop one to 0 hit points, it instead just teleports away to a harmless demiplane where it recovers for a time before returning to the Material plane. Reducing an arch hag to 0 hit points buys you at least 2d6 arch hag free days—but if you were within 60 feet of the arch hag when the “killing blow” was struck, you’ll be cursed with Disadvantage on skill checks and saving throws (and the arch hag knowing your exact location anywhere in the multiverse).
If you want to slay an arch hag forever, you have to figure out what its anathema is—this is the thing that an arch hag hates most in the world. It could be anything. It could be the pure love of a child for its mother or like the venom from one particular giant spider demon. It varies from hag to hag. But once you find what the anathema is, you have to then kill the arch hag while the arch hag is within 30 feet of the anathema, or else get ready to try again in at least 2d6 days.
Lich
A classic recurring monster. Liches are famous for not dying when you kill them. This is in part because they are already undead. But also because they keep their essence locked away in a special spirit jar which houses their ability to return, even from disintegration.
Only by finding and destroying a lich’s spirit jar can you permanently slay one. Otherwise, they just keep coming back, gaining a new body at full capacity after 1d10 days. So, good luck trying to find the spirit jar in the first place.
Rakshasa
Rakshasa have a long history of being immortal except for one weird trick. It used to be a blessed crossbow bolt was the only way to take one out. And then, such a crossbow bolt would instantly take one out. These days, though, Rakshasas aren’t especially vulnerable to blessed weapons like that.
Instead, they just skate by on Fiendish immortality. If you kill a Rakshasa outside of the Nine Hells, it just instantly reforms a new body at full hit points somewhere in the vastness of the Nine Hells. It doesn’t even have to be the same place. In order to kill a Rakshasa, you have to somehow track it down to the Nine Hells (or trick it into going there in the first place) and kill it while there.
Death Knight
Death Knights are a new one. These were once powerful warriors who were twisted by evil and became tormented by the villainies they committed in life. Now these fell beings live a tormented life where they are tortured for their evil by… having awesome powers and being unkillable and commanding legions of undead.
Seems like an “awful” “torture.” Someone should really feel for them. Because the only way you can kill a Death Knight is to get it to atone for its evil deeds – if it hasn’t, then killing one just gives you 1d10 days to prepare before the Death Knight comes back, fully restored, in a location significant to the Death Knight (probably a dread citadel somewhere).
Blob of Annihilation
And then there’s the Blob of Annihilation. This massive slime is an ooze of “cosmic entropy” gooped up around the remains of one or more dead deities. They engulf and consume whole villages—and are often summoned by nihilistic cults or magic users going for the collateral damage high score.
But even if you manage to kill one of these, you still won’t peranently defeat one. They just implode and coat everything in slime while also pulling anything engulfed by it into the astral plane. And then 1d20 days later, the blob comes back, reforming on a random world within the material plane.
There is no way to permanently destroy one of these, as the rules are written.
Of course if YOU try to become immortal, it’s somehow “cheating”!
