You craft an illusion that takes root in the mind of a creature that you can see within range. The target must make an Int saving throw. If failed, you create a phantasmal object, creature, or other visible phenomenon of your choice that is no larger than a 10' cube and that is perceivable only to the target. This spell has no effect on undead or constructs. The phantasm includes sound, temperature, and other stimuli, also evident only to the target. The target can use an action to examine the phantasm with an Int (Investigation) check against your spell save DC. If successful, the spell ends.

The target treats the phantasm as if it were real, and can even take dmg from it. A phantasm appearing as a creature can attack the target. Similarly, a phantasm created to appear as fire, a pool of acid, or lava can burn the target. Each round on your turn, the phantasm can deal 1d6 psychic dmg to the target if it is within 5' of the phantasm, provided that the illusion is of a creature or hazard that could logically deal dmg.