Larvitar (5e Creature)
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Small elemental, any alignment
Earth Glide. The larvitar can burrow through nonmagical, unworked earth and stone. While doing so, the larvitar doesn't disturb the material it moves through.
Guts. The larvitar has advantage on saving throws against being charmed or frightened, and while charmed or frightened, it has advantage on attack rolls.
Sand Veil. While in sandy terrain, the larvitar has advantage on Dexterity (Stealth) checks, and can take the Hide action as a bonus action.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) piercing damage