Monster Manual, page 124
Earth Elemental CR: 5
Large elemental, neutral
Armor Class: 17
Hit Points: 126 (12d10+60)
Speed:
30 ft
, burrow: 30 ft
Skills: Proficiency Bonus +3
Damage Vulnerabilities: thunder
Damage Resistances: bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities: poison
Condition Immunities: exhaustion, paralyzed, petrified, poisoned, unconscious
Senses: Darkvision 60 ft, Tresmorsense 60 ft, Passive Perception 10
Languages: Terran
Challenge Rating: 5
Earth Glide. The elemental can burrow through nonmagical, unworked earth and stone. While doing so, the elemental doesn't disturb the material it moves through.
Siege Monster. The elemental deals double damage to objects and structures.
Actions
Multiattack. The elemental makes two slam attacks.
Slam. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage.
Suggested Environments
Underdark