According to RL Science, it should float, and float pretty high in the water, too. Dragon Magazine #124 states that gelatinous cubes can move around in water “freely”, but their acid is diluted.
How do gelatinous cubes move?
The cube moves up to its speed. While doing so, it can enter Large or smaller creatures’ spaces. Whenever the cube enters a creature’s space, the creature must make a DC 12 Dexterity saving throw. On a successful save, the creature can choose to be pushed 5 feet back or to the side of the cube.
Can a creature enter a gelatinous cube?
The cube takes up its entire space. Other creatures can enter the space, but a creature that does so is subjected to the cube’s Engulf and has disadvantage on the saving throw. Creatures inside the cube can be seen but have total cover. A creature within 5 feet of the cube can take an action to pull a creature or object out of the cube.
What happens when you push a gelatinous cube?
Whenever the cube enters a creature’s space, the creature must make a DC 12 Dexterity saving throw. On a successful save, the creature can choose to be pushed 5 feet back or to the side of the cube. A creature that chooses not to be pushed suffers the consequences of a failed saving throw.
Can a gelatinous cube climb a wall?
Although incapable of climbing walls, particularly large gelatinous cubes could also absorb mold and moss from ceilings. Organic material was quickly dissolved in the acidic ooze that made up the cube’s body, while bones and inorganic matter spent some time floating within the creature until eventually expelled.
How does a gelatinous cube work in dungeons and Dragons?
On a failed save, the cube enters the creature’s space, and the creature takes 10 (3d6) acid damage and is engulfed. The engulfed creature can’t breathe, is restrained, and takes 21 (6d6) acid damage at the start of each of the cube’s turns. When the cube moves, the engulfed creature moves with it.
