For The Hive. When reduced to half health, the swarm will spit out spores and acid 30ft in front of it. Any creatures in its path take 46 (12d6) acid damage.

Glow. The swam emits 15ft radius of bright light and 25ft radius of dim light.

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 zurk. The swarm can't regain hit points or temporary hit points.

Bloodfeast. A creature that starts its turn in the swarm's space lose 14 (4d6) hit points due to blood loss or 7 (2d6) hit points if the swarm is at half hit points or fewer.

Multiattack. The zurks use Blood Drain. If the attack misses, they make four pincer attacks or two pincer attacks when the swarm has half hit points or less.

Blood Drain. Melee Weapon Attack: +10 to hit, reach 5 ft., one creature. Hit: 32 (8d6 + 4) piercing damage or 18 (4d4 + 3) piercing damage when the swarm is at half hit points or fewer. 

Pincer. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature. Hit: 10 (2d4 + 6) piercing damage.