Wekdieri

Crushing Break. When the Wekdieri flies towards a creature from at least 20 feet away and makes a melee attack, the Wekdieri can choose to lose all movement it has left, converting it into bludgeoning damage. Every creature in a 5 foot radius other than the Wekdieri must make a DC 16 Strength Saving Throw, taking xd6 bludgeoning damage and being knocked prone on a failed save, or half as much and not being knocked prone on a successful save, where x is a tenth of it's movement speed it sacrifices.

Spellcasting. The Wekdieri's innate spellcasting ability is Intelligence (spell save DC 13). The Wekdieri can innately cast the following spells, requiring no material components:
At will: bane, darkness, ray of frost
1/day each: acid arrow, blur, chill touch, ray of frost, stinking cloud

The target of the command spell does not have to understand the Wekdieri.

Multiattack. The Wekdieri makes two rend attacks and one clasp attack if possible.

Rend. Melee Weapon Attack: +7 to hit, reach 5 ft., 1 target. Hit: 9 (3d4 + 1) piercing damage.

Clasp. Melee Weapon Attack: +7 to hit, reach 5 ft., 1 target. Hit: 5 (2d4) necrotic damage and the target is grappled, this can only be used while afloat.

Knot Spout (Recharge 5-6). The Wekdieri spits out a volume of tentacles up to 60 feet away, creating a Rancid Knot at the location. All creatures within a 10 feet radius of the attack must make a DC 16 Constitution Saving Throw, taking 32 (7d8) necrotic damage and becoming poisoned on a failed save, or taking half as much and not being poisoned on a successful one.