Multiattack. The ape makes two Fist attacks.
Fist. Melee Attack Roll: +9, reach 10 ft. Hit: 22 (3d10 + 6) Bludgeoning damage.
Boulder Toss (Recharge 6). The ape hurls a boulder at a point it can see within 90 feet. Dexterity Saving Throw: DC 17, each creature in a 5-foot-radius Sphere centered on that point. Failure: 24 (7d6) Bludgeoning damage. If the target is a Large or smaller creature, it has the Prone condition. Success: Half damage only.
Leap. The ape jumps up to 30 feet by spending 10 feet of movement.