Swampgas Bubble

Bludgeoning Bounce. Whenever the swampgas bubble is subjected to bludgeoning damage, it takes no damage and instead is pushed up to 10 feet away from the source of the bludgeoning damage. If the bubble is subjected to bludgeoning damage while attached to a creature, the bubble must succeed on a DC 13 Strength saving throw or detach from the creature and be pushed up to 5 feet away.

Fiery Death. If the swampgas bubble has half its hp or fewer and takes any fire damage, it dies explosively. Each creature within 20 feet of the bubble must make a DC 13 Dexterity saving throw, taking 7 (2d6) fire damage on a failed save, or half as much damage on a successful one.

Pseudopod. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage plus 4 (1d8) poison damage.

Suffocating Grasp. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 6 (1d6 + 3) bludgeoning damage. If the target is Medium or smaller, the swampgas bubble attaches to the target's head, and the target is blinded while the bubble is attached. While attached, the bubble can't make pseudopod attacks against the target. At the start of each of the bubble's turns, the target takes 9 (2d8) poison damage and begins suffocating as it breathes in the poisonous gases within the bubble. A creature is affected even if it holds its breath, but creatures that don't need to breathe aren't affected. The bubble can detach itself by spending 5 feet of its movement. It does so if its target falls unconscious or dies. A creature, including the target, can take its action to detach the bubble by succeeding on a DC 13 Strength check.