scarlet edge
Description: Dying instead starts a timer lasting X seconds, during which your hp stays at exactly zero. Killing enemies and damaging bosses increases the timer. Getting hit greatly decreases the timer. Kill an elite or boss to set yourself back at 1 hp in an otherwise normal state.
Details: (I'm referring to being on the timer as being half-dead)
X scales with 
. (I'm thinking 30 seconds at start of game, scaling to 120 by endgame.)
If you revive in this manner and die again in the same biome, the timer starts where it left off. The timer resets when entering a corridor.
Killing enemies/damaging bosses has diminishing returns with staving off the timer. This also resets when entering a corridor. This could also scale with .
If the ingame timer is paused, the death timer is also paused.
You cannot remove this mutation if you enter a corridor while in this half-dead state. When you enter the next biome you will still be at 0hp and half-dead but your timer and any diminishing returns on increasing it reset back to the "maximum".
Traditional healing (e.g flasks, wdkm etc) does not work while half dead.
The amount of timer decreased on hit is linked to how much of your max hp the hit would have done. (1% = 1 second, all damage instances do at least 1 second of damage to the timer).
While at 10 seconds or less the screen gradually darkens and skeletal hands on the border of the screen start reaching for the Beheaded.
Getting set back to 1 hp does not count as healing for the purpose of Dead Inside preventing it.
(optional) Normally the name of the mutation is Dying Gasp but if you look at it while half-dead it's called Reaper's Sprint instead and has a different icon.
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