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I encountered a weird glitch in Warzone Firefight the other day where a Sangheili (elite) actually hijacked a Spartan on a warthog turret seat. Obviously it was never meant to happen but as you can see they don’t even have any animation or poses for the warthog. They have to completely redo the entire model of the elite to make it playable, something that’s hard to do when using a new engine. Hopefully when Halo 6 is released they have a model for the elite that works on every pick up item and vehicle sothey can become playable. The only other thing that seems to have the possibility of being playable are the Promethean soldiers which would be fun to play as. They could fit perfectly with a few model tweaks.