Swarm of Corpse Worms (5e Creature)
From D&D Wiki
Swarm of Corpse Worms
Medium swarm of Tiny beasts, unaligned
Skills athletics+2, perception +2
Amphibious. The swarm can breathe air, water, and blood.
Blood Vision The swarm can see through blood as if clear air.
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 insect. The swarm can't regain hit points or gain temporary hit points.
Bites. Melee Weapon Attack: +2 to hit, reach 0 ft., one creature in the swarm's space. Hit: 20 (4d8) piercing damage, or 10 (2d8) piercing damage if the swarm has half of its hit points or fewer.
Black Tentacles The swarm manifests the spell Black Tentacles around itself or their foe. (With a Range of 90 feet.)
Drive Corpse The swarm can enter into a corpse and animate it in 1d4 (an extra 1d4 added on for every size category above Small) turns as a Hollowed Carrier, though it can only animate the corpse in such a way if threatened or no other corpses are nearby. (If left like this for a week will become a Bloated Hollowed Carrier and the swarm returns to full size)
A swarm of necrotic magical insects that feed off the corpses of the dead with a preference for fresh carcasses that normally resides within planes of existence where rivers of blood are common, using such as their primary home when corpses aren’t available. In the wilds of other planes swarms of corpse worms congregate in the bodies of massive creatures, and when the corpse is running out of room they begin to seek out new bodies to latch unto in their search for a sustainable food source.