Combating the yutyrannus is made quite simple with a good argentavis. Simply fight it while it's busy with another animal, or grab a deer as bait. Hover overhead and wait for it to roar, then rough it up during the cooldown. If it's a higher level, then quickly fly above its range and wait for it to roar some more before going down and finishing the job. Grab more bait animals as necessary and keep an eye on your stamina. If you get cause by the fear roar and run out of stamina, you will land and be in an awful lot of danger.

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