I think I got it.
// If the enemy is doing a special attack and if we allow coin flip deaths then take damage
const Game_Battler_GainHp = Game_Battler.prototype.gainHp; // BODY
Game_Battler.prototype.gainHp = function(value) {
if (this.isActor() && !isDeathEnabled()) {
value = value < 0 ? 0 : value;
}
Game_Battler_GainHp.call(this, value);
};
This is the part,right isn't?