Death warping is warping to the beginning of an area after you die. Death warping unlike Void Warping takes you to that last place you entered the area even if you went through a door since you last entered it. In some places, it takes you further back than the beginning of the area. You regain control of Link 11 seconds after you die. Burning and freezing and running into a gold skulltula are very fast ways to lose health, which is really useful in a Majora's Mask 100% speedrun because heart pieces are required and each time you get one, it fully restores your health. If you have the double defense upgrade, any method of damaging yourself can only be done half as fast. Any attack that took away 1/4 of a heart before the upgrade takes away 1/8 of a heart after despite the fact that the 1/8 hearts don't show. Also, Link's drowning timer starts at the number of seconds equal to the number of eights of a heart he has whether or not he has the double defense upgrade.