Baby Owlbear Swarm

Keen Sight and Smell. The owlbear swarm has advantage on Wisdom (Perception) checks that rely on sight or smell.

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

Swarm Susceptibilities.   The baby owlbear swarm is susceptible to area damage.  Any Roll damage for each square in the baby owlbear swarm's space for area damage.

Dispersal.  Once the hp of the baby owlbear swarm is reduced to zero, the swarm disperses.  1d10 baby owlbears are left.

Rumble. If the owlbear swarm moves into, through or out of a creature's square, that target must succeed on a DC 12 Strength or Dexterity saving throw or be knocked prone. If the target is prone, the owlbear swarm does an automatic (2d6) bludgeoning damage.

Prone to Panic. The swarm starts encounters as pacified and moves at half speed.  If a pacified swarm is attacked or startled, it becomes panicked.  All other activity around the swarm requires an Animal Handling skill check of DC 12 or else the pacified swarm becomes panicked.  To start the round, a panicked swarm will always move away from what startled it.  At the end of the round, a panicked swarm becomes enraged unless an Animal Handling skill check of DC 14 is made, in which case the swarm remains panicked; if a DC of 18 or higher is made, the swarm returns to pacified.  If a swarm is enraged, an Animal Handling skill check of DC 16 must be made to return the swarm to a panicked state; a DC of 20 or higher will return the swarm to a pacified state.

Enraged Frenzy. If the swarm is enraged, it will attack all targets within its space.  Melee Weapon Attack: +3 to hit, reach 0 ft., area targets. Hit: 9 (2d6 + 2) slashing damage.