Reaper Bird (the bird of death)

This bird would spawn in family groups of 2-6 in Jungle biomes (and variants). It would stand two blocks tall, be very colorful, and be somewhat ostrich shaped but with larger beaks and claws. Reapers would be flightless but able to jump up to three blocks up and never take fall damage.

When a player approached a reaper, it and any reapers nearby would turn to the player and start flapping and screeching. If the player got too close to one of them, all the Reapers would attack together. Any attack that hit a Reaper would make all the Reapers in the area go agro toward the attacker.

If a Reaper's target was out of reach, the Reaper would leap and attack at the height of its jump.