Mucous Salamander

Armor Class 13 · Hit Points 44 (8d8 + 8) · Speed 30 ft., climb 30 ft. (solid form), swim 50 ft. (liquid form)

Shifting Molecules (Trait). When the salamander enters or exits water, it changes the form of its molecular structure to mimic its surroundings. Other than its AC, its statistics are the same in each form. Any object it is wearing or carrying isn't transformed.

Amphibious (Trait). The salamander can breathe air and water.

Diffuse Body (Trait). The salamander can move through other creatures and objects no more than 10 feet in diameter as if they were difficult terrain. It takes 5 (1d10) kinetic damage if it ends its turn inside an object.

Spider Climb (Trait). The salamander can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Spiked Hide (Trait). Any creature that grapples the salamander takes 3 (1d6) kinetic damage at the end of its turn.

Watery Stealth (Trait). While underwater, the salamander has advantage on Dexterity (Stealth) checks made to hide, and it can take the Hide action as a bonus action.

Bite (Action). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 2) kinetic damage.

Claw (Action). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 8 (1d10 + 3) kinetic damage.