Cassowaries (火食鳥 Hikuidori) are the personal summoning of Kaito Hiroki, and hailed as the deadliest bird on the planet.
Cassowaries are very large flightless birds that naturally appear in tropical regions of the Shinobi world. The Cassowary is the third tallest and second heaviest living bird, smaller only than the ostrich and emu. Many summoned Cassowary can speak, and some can use jutsu. Cassowary possess incredible speed, capable of reaching up to 30mph, and leg strength, allowing it to jump 5 feet into the air, it's an accomplished swimmer, excelling at both the breast and butterfly stroke. And their kick may be the last thing their opponent sees because the end of the foot possesses a razor sharp, 6 in. long claw that can easily rip the insides out of a human. If this fails,it can still cause massive internal bleeding and organ damage, which if not treated, can cause a slow and painful death. It also possesses an armored head.