Glacial Crawler

Acidic Coating. A creature that touches the crawler or hits it with melee attack while within 5 ft. of it takes 9 (2d8) acid.

Amphibious. Can breathe air and water.

Snow Camouflage. Has advantage on Dex (Stealth) checks made to hide in snowy terrain.

Tunneler. Can burrow through ice snow and permafrost and leaves a 5 ft. diameter tunnel in its wake.

Multiattack. 2 Bites and 1 Tail Spike or 3 Superheated Acid Spits.

Bite. Melee Weapon Attack: +9 to hit, 10 ft., one creature,. 16 (2d10+5) piercing damage + 9 (2d8) acid.

Tail Spike. Melee Weapon Attack: +9 to hit, 10 ft., one creature,. 19 (4d6+5) piercing damage. Target is grappled (escape DC 17) if it is a Large or smaller creature and crawler doesn't have another creature grappled.

Superheated Acid Spit. Ranged Weapon Attack: +7 to hit, 60 ft., one creature,. 12 (2d8+3) acid + 9 (2d8) fire.

Acidic Spray (Recharge 5-6). Spews superheated digestive juices in a 30' cone. Each creature in that area: 18 (4d8) acid and 18 (4d8) fire and is coated in heated acid (DC 17 Dex half damage and isn't coated in acid). A creature coated in heated acid takes 4 (1d8) acid and 4 (1d8) fire at start of each of its turns. A creature including coated target can take its action to wash or scrub off the acid ending the effect.