Price 40,000 gp; Slot none; CL 13th; Weight 37 lbs.; Aura strong conjuration
Set in the center of this dark steel altar is an eye-shaped, obsidian lens. Many-eyed horrors from dark spaces between the stars stare back through the lens. When viewed from different angles, the altar’s proportions seem to change as though space were bent around the object.
Whenever a creature within 60 feet of the altar casts a summon monster or summon nature’s ally spell (or uses either spell as a spell-like ability), the creature can use the altar as a focus for the spell. Any creatures summoned this way emerge from the dark lens, appearing adjacent to the altar. The creatures are strangely mutated, gaining the benefit of lesser evolution surge as though they were eidolons with no base form. They still must meet all prerequisites for an evolution, including having particular natural attacks, and they count as the eidolons of a summoner with a summoner level equal to the level of the summoning spell for the purposes of satisfying prerequisites and determining how many total attacks per round they can use.
There is a 25% chance that any creature summoned through the lens attempts to kill the summoner rather than obeying the summoner’s commands. Roll once per casting for all creatures summoned, and if the creatures turn on their summoner, the summoner can’t dismiss the spell as normal (though it still expires when the duration ends).
When the summoned creature appears, the planar rift through which it passes creates a vacuum near the altar for 1 round. Each creature within 5 feet per level of the summoning spell is affected by a severe blast of air (as per gust of wind) directed toward the altar. A summoning spell of 4th level or higher creates a more powerful vacuum; all creatures within the area are treated as one size category smaller for the purpose of determining how the vacuum affects them. If the summoning spell is 7th level or higher, the creatures are treated as two size categories smaller. If a creature summoned through the altar is ever forced into the altar’s space, including by the vacuum effect, the summoning instantly ends as the creature is sucked back to its home dimension.
Pathfinder Roleplaying Game Horror Adventures © 2016, Paizo Inc.; Authors: John Bennett, Clinton J. Boomer, Logan Bonner, Robert Brookes, Jason Bulmahn, Ross Byers, Jim Groves, Steven Helt, Thurston Hillman, Eric Hindley, Brandon Hodge, Mikko Kallio, Jason Nelson, Tom Phillips, Stephen Radney-MacFarland, Alistair Rigg, Alex Riggs, David N. Ross, F. Wesley Schneider, David Schwartz, Mark Seifter, and Linda Zayas-Palmer.