If you have a tribe-Have a friend carry you on an argentavis, and shoot it till it goes down.

If you're alone- you can: make a trap out of wood or stone with a bethemoth gate with a box inside so you can shoot it safely.

Or you could: make a ballista and a chain bola to subdue it then shoot it down.

Or wildly shoot it and run and hope for the best :)

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