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Player > Spells > Usher Apocalypse
Starfinder Character Operations Manual p.142
Level Witchwarper 6
School illusion (shadow)
Casting Time 1 standard action
Range long (400 ft. + 40 ft./level)
Area 60-ft. radius
Duration 1 round/level (D)
Saving Throw Will disbelief and Reflex partial; see text; Spell Resistance yes
You create a quasi-real apocalypse to tear through the area,
causing several effects. When the spell first takes effect,
illusory hellfire crashes to the ground, dealing 6d6 fire
damage to your enemies in the area. Creatures can attempt
a Will saving throw to disbelieve the fiery vision and take
only half damage.
Then, for the duration, two more effects continue. An illusion
makes the ground appear to be unstable crust over lava, which
your foes treat as difficult terrain. Grasping hands appear to
reach out from the ground to grab at enemies. Each time an
enemy starts its turn in the area, it must succeed at a Reflex
saving throw or be unable to leave its space for the turn.