The Tidebound Sea Cave

• A1 × Aboleth (CR 10, 5,900 XP)
• B3 × Chuul (CR 4, 1,100 XP each)

XP

9,200 of a 9,200 XP moderate budget

Party

4 characters of level 10

Barrels marked with a merchant's seal bob in the shallows, all of them open. The air tastes of salt, tar and fish left too long in the sun.

Setup. Three chuuls led by an aboleth are whispering into the minds of anyone who comes near, promising answers.

Terrain

• Sea fog: everything beyond 30 feet is Lightly Obscured.
• Slick rocks: the wet rocks are Difficult Terrain; a creature shoved on them must succeed on a DC 14 Dexterity saving throw or fall Prone.

Tactics. They speak telepathically during the fight, offering secrets in exchange for mercy.

Twist. A villager hired the party to clear this area, but the creatures claim they were here first, and they have a deed.

Adjust on the fly

• Easier: Remove one chuul (−1,100 XP).
• Harder: Add one more chuul (10,300 XP total, high for this party).

Treasure. 3,200 gp in mixed coins and two gemstones worth 320 gp each; Potion of Greater Healing.