Geodic (5e Creature)
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Large elemental, neutral
Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks
False Appearance. While the geodic remains motionless, it is indistinguishable from a normal boulder.
Multiattack. The geodic makes two slam attacks. If both attacks hit a Medium or smaller target, the target is grappled (escape DC 15), and the geodic uses its Engulf on it.
Slam. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage.
Engulf. The geodic engulfs a Medium or smaller creature grappled by it. The engulfed target is blinded, restrained, and unable to breathe, and it must succeed on a DC 15 Constitution saving throw at the start of each of the geodic's turns or take 14 (2d8 + 5) bludgeoning damage. If the geodic moves, the engulfed target moves with it. The geodic can have only one creature engulfed at a time.
Geodics are boulder-like creatures of elemental earth that spend most of their time curled up, all but indistinguishable from ordinary boulders. While a geodic is dormant, it remains still as a stone, but when it is threatened, it unfurls and wraps around its foes before it crushes them to death. Much like a geode, the inside of a geodic is lined with glittering crystals, though the elemental must be killed before this bounty can be retrieved.
Elemental Nature. A geodic doesn't require air, food, drink, or sleep.