Pretty easy tame. I recommend using an argentavis or desmodus to aggro it. Then fly away but stay in aggro range. Lure it to a nice sized rock that it cannot get on then land. Dismount on rock and use any gun you can equip tranq darts with to knock it out. once it starts running fly your mount to the ground, dismount again and keep shooting. You can totally tame this with one player it will just be slightly more difficult.

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