Otiluke's Death Screen

This spell calls into existence an immobile gray, misty screen, shaped as the caster wills (20 x 20 feet is common). Any creature passing through the screen suddenly finds itself trapped in a mysterious zone of nil-space where it is subjected to anti-energy drawn from one of the four Negative Quasi-Planes.

Every round, the trapped creature loses 25% of its current hit point total, dropping to 0 hit points at the end of the 4th round if it fails to escape. The creature dies at -10 hit points at the end of the 5th round. For every round a creature is trapped, it receives a saving throw vs. death magic. Success means the creature escapes back to the Prime Material Plane, emerging from the side of the screen opposite the side entered. The saving throw to escape is made at -1 in the 1st round, -2 in the 2nd, -3 in the 3rd, and -4 in the 4th round.

If the spell ends before a creature escapes or dies, the creature is released onto the Prime Material Plane as the screen disappears, as if the creature had escaped on its own. A creature re-emerging injured but alive is stunned for 1d4 rounds as it recovers from the effect of the life-draining zone. Those imprisoned in the zone can heal themselves and use any other magics, but can't escape unless they make saving throws for the zone.

The material components are a sheet of lead crystal, earth from a vampire's coffin, and a hollow sphere (for vacuum).

Notes: Uncommon or rare spell (WoG).