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The Beast Handlers are Imperial Legionaries tasked with handling the Beasts aboard the Leviathan, whether it be the Loyalist War Beasts or the Royal Beasts. They are exclusively seen in the Pleasure Gardens.
They appear in the first segment, where the Fireteam must clear the Gardens of any hostiles, including the Beast Handlers and their Loyalist War Beast back-up. They also appear during the Royal Beasts when a flowering plant is blasted, with one on one side armed with a Cabal Headhunter to try and eliminate the Crystal-bearers, while the other on the other side attempts to kill the Pollen-bearers below. It is the Crystal-bearers' duty to eliminate these Legionaries as soon as possible (killing the one below won't trigger a Beast, even if the Legionary is killed right in front of it.)
List of appearances