You plunge the targets’ minds into a veiled immersive mindscape (see page 235) of your own design. You can affect any number of creatures whose combined total Hit Dice do not exceed 30. A creature of 10 HD or fewer gets no saving throw, one of 11–15 HD escapes after 10 minutes per level you possess on a successful save, and a creature of 16 HD or more negates the effect on a successful save. Given time, the bodies of creatures whose minds are trapped in a _microcosm_ can die of starvation and thirst without care. Creatures can neither escape from nor enter a _microcosm_, even via a [_mindscape door_](/spells/mindscape-door). _Microcosm_ can be ended only by [_miracle_](/spells/miracle) or [_wish_](/spells/wish).
Creatures inside a _microcosm_ can be affected by mind-affecting effects targeted against their real bodies. However, they perceive them as natural events within their inner mindscape. Multiple creatures affected by the same _microcosm_ can interact with one another within the mindscape.