Apex Corpse Form

Become an apex undead body. You are immune to poison and necrotic damage, resistant to cold and nonmagical weapon damage, regenerate hit points equal to your CON modifier at the start of each turn unless you took radiant damage, and your Corpse Physiology powers deal or prevent extra damage once per turn.

This power has its own stable page so it can be linked from any character, item, location, story post, bargain, curse, or future reward.