Air Spirits

Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny creature. The swarm can't regain hit points or gain temporary hit points.

Condensing. The Air Spirits can join together to form a platform to stand on. They can't maintain this form for more than a few seconds, so if a creature ends its turn on top of it, it will fall to the ground taking fall damage as normal.

Hostile takeover. If a hostile creature to the Air Spirits enters their space, they will use their reaction to attack it. If the attack is successful, the attacked creature's speed drops to 0 until the start of its next turn.

Aerial Cuts. Melee Weapon Attack: +5 to hit, reach 5 ft., one target in the swarm's space. Hit: 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the Air Spirits has half of its hit points or fewer.