# Aboleth ## Regional effects _Source: Monster Manual (2024)_ The region containing an aboleth's lair is warped by it, creating the following effects: - **Foul Water.** Water sources within 1 mile of the lair are supernaturally fouled. Creatures other than the aboleth and its allies that drink such water must succeed on a DC 15 Constitution saving throw or have the [Poisoned](3-Mechanics/CLI/rules/conditions.md#Poisoned) condition for 1 hour. - **Psionic Projection.** While in its lair, the aboleth can cast [Project Image](3-Mechanics/CLI/spells/project-image-xphb.md), requiring no spell components and using Intelligence as the spellcasting ability (spell save DC 16). When casting the spell this way, the spell's range is 1 mile, and the aboleth can use its telepathy as if it were in the illusion's space. If the aboleth dies or moves its lair elsewhere, these effects end immediately.