One more lingering bug for you unfortunately.

When you're in grace state you have the effect of having halved max HP. When you hit Critical it seems to slow you and also continue having the halved HP.

But in several mods AND vanilla there are ways to negate a fatal damage hit. Stuff such as totems of undying. Corail Tombstones soul receptacles. Inventory Pets Slime pet. Cyclic Soulstone. Extra utiltiies Second chance potion. Potion Core Revival potion.

When it comes to dieing to critical phase and saving yourself by making or collecting one such of these death protection items the items seem to have their full effects however the attribute of halved health and the slow from critical phase all seem to linger afterwards. The Regenerations being deleted on death config option also triggers removing the rest of your regens despite not actually dieing.

Would it be possible to have the stats get reset when the tick of damage is applied to kill the player instantly regardless of death or not, and have the regenerations getting deleted attempt to detect a properly dead or perhaps a respawning player before attempting to removing the regenerations so players can use their death protections from other mods if they desire? (if they just really really don't want to go and want to preserve their genetic effects and have no other way)

If not for 1.12.2, but for your later versions, consider it. Maybe stick a hidden achievement on it if they critical die and don't actually die.

Fixed by @Jackiecrazy

aye. 👍