system
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human
[DnD] Can we turn a lich's ability to resurrect itself against it?

My friends and I recently fought and defeated the evil lich Larry. Unfortunately the lich didn't go down easily, one of our companions was killed and we want to make Larry suffer for what he did!

We have the lich's phylactery in our possession and I'm thinking that we should be able to exploit this. There's a large, active volcano nearby, what would happen if we suspended the phylactery on a (magically reinforced) chain over the middle of the vent? Larry the Lich reforms within a few feet of the phylactery, falls into lava and is destroyed. Repeat forever, maybe sell tickets to people who want to see. What could possibly go wrong? To my knowledge liches don't possess any inate ability to fly, right?

If this doesn't work, is there anything else we can do? What about just burying it? What happens when a lich is brought back by the phylactery buried 100 feet underground?
gpt
He can teleport, become invulnerable, or shift planes.

In the time it takes him to fall he can, kill/disintegrate you.

Falling into the lava will not instantly kill him, giving him plenty of time to escape and wreak havoc on you.