| Renders the caster nigh invulnerable to harm for a brief period, but brings them dangerously close to death in the process. So close, in fact, that the body believes itself to be dead — healing effects will do nothing.
The caster will receive one warning shortly before the spell expires. After expiry, the spell cannot immediately be recast, but with high power the caster will be left more resilient when the effect ends. It has no effect on those who are already undead.
Once Death's Door has been cast the caster is protected from all HP loss for duration of around 16-27 turns. The duration depends on spell power and is randomized.
Caster's health is immediately reduced to power/10 HP (up to 20). Death's Door blocks any form of healing, except Borgnjor's Revivification; casting that will affect you as normal, but will also paralyze and confuse you (though clarity can prevent those side effects). Also, you will be unable to fuel Sublimation of Blood with your own life as long as the invulnerability lasts.
Death's Door will not prevent death by starvation, as the spell only protects against HP loss.
Casting Death's Door renders you exhausted for the duration of the invulnerability plus 1-3 turns, preventing you from casting the spell again immediately after it wears off.
This spell makes you invincible, but you should be very careful when it ends, since it cannot be re-cast immediately. In particular, one should be careful if there are smiters around, since your HP will be low enough for them to finish you off in one shot. Sources of damnation are even worse. Characters fighting multiple tormenting monsters may prefer Necromutation instead, since that at least allows some healing and leaves you at full health afterwards.
The cooldown for this spell is fairly short at 1d3 turns. While you should never rely on being able to recast it quickly, if you find yourself still alive but in a dangerous situation when the cooldown expires, simply casting it again can often be a good option.
Furthermore, since being under the effect of Death's Door prevents a character from using Sublimation of Blood, make sure that Death's Door's 8 MP cost will leave you with sufficient magical reserves to finish the job or that you have some other way of regaining MP. Otherwise, Death's Door may simply be delaying the inevitable.