Book of Ronin

Level 9 Codex Grimoire. Recall Cost 4.

Transform: Make a Spellcast Roll (15). On a success, transform into an inanimate object no larger than twice your normal size. You can remain in this shape until you take damage.

Eternal Enervation: Once per long rest, make a Spellcast Roll against a target within Close range. On a success, they become permanently Vulnerable. They can't clear this condition by any means.