Strength of the grave

When damage reduces you to 0 hit points,
you can make a Charisma saving throw
(DC 5 + the damage taken). On a success,
you instead drop to 1 hit point.
You can't use this feature if you are reduced
to 0 hit points by radiant damage or by a
critical hit.
After the saving throw succeeds, you can't
use this feature again until you finish a long rest.