Ungodly Abomination (small)

Conjoin. At any time, an Ungodly Abomination can conjoin to any other of its type. The creature it attaches to heals itself by the amount of hp that the original Ungodly Abomination possessed before conjoining itself. The two creatures then become one, and gain a total amount of tentacles equal to the sum of each of their previous amount of tentacles combined. This costs 10 feet of movement.

Malleable Flesh. When attacked with any weapon that does piercing damage, the weapon shall stay attached to the creature. It takes an action to remove, with a strength check of DC of 12 to get it out. If what pierces it is a piece of ammunition, failure to meet a dexterity check of DC 10 will result in breaking it. 

Reactive Tentacles. Can make as many attacks of opportunity as they have current appendages. 

The Unholy Abomination can make 3 attacks with its' tentacles. Tentacle sword costs 1 weapon modding action to make, and uses 2 attacks to use. 

Weapon Modding. The Ungodly Abomination can combine tentacles to create new attacks. 

Tentacle Skewer. Melee Weapon Attack: +5 to hit, reach 5 ft., 1 target. Hit: 5 (1d6 + 1) piercing damage. 

Tentacle Shortsword. Melee Weapon Attack: +5 to hit, range 5 ft., 1 target. Hit: 10 (2d6 + 2) slashing damage.