Golisopod (5e Creature)
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Medium elemental, any alignment
Amphibious. The golisopod can breathe air and water.
Coward. The golisopod has disadvantage on saving throws against being frightened
Emergency Exit. The golisopod can take the Dash, Disengage, or Hide action as a bonus action.
First Impression. If the golisopod surprises a creature and hits it with an attack during the first round of combat, the target takes an extra 10 (3d6) damage from the attack.
Multiattack. The golisopod makes two Liquidation attacks.
Liquidation. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage. If the target is a creature, it has disadvantage on all attack rolls until the end of its next turn.
Iron Defense. When a creature hits the golisopod with an attack, it can use its reaction to force the creature to reroll the triggering attack with disadvantage.