Amalgam

Amphibious: The creature can breathe air and water.

Detect Life: The creature can magically sense the presence of living targets up to 5 miles away. It knows the general direction they’re in but not their exact locations.

Insanity: The creature has advantage on saving throws against being charmed or frightened.

Limited Telepathy: The creature can magically communicate simple ideas, emotions and images telepathically to any target within 100 feet if that target understands at least one language.

Pack Tactics: The creature has advantage on an attack roll against a target if at least one of the creature’s allies is within 5 feet of the creature and the ally isn’t incapacitated.

Failed Experiment: Each amalgam lives in a perpetual state of rot and decay. Melee attacks made by the creature deal extra necrotic damage.   

Multiattack: The amalgam makes one bite and one claw attack.

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., 1 target. Hit:  (2d6 + 3) piercing  damage. The target must make a dc 15 con save or take 1d6 necrotic damage . 

Claw. Melee Weapon Attack: +5 to hit, reach 5 ft., 1 target. Hit: (1d6+3) slashing damage. The target must make a dc 15 con save or take 1d6 necrotic damage.

Mark: The amalgam telepathically marks a single creature. All amalgams can track the creature for 1 hour.