The best way for me to tame a Tapejara is to have lots of rare flowers, eat them, get on a flying dino (any) and get it in a taming pen, or if you don't have the resources to build one, have lots of bolas and keep throwing them at it, when the rare flower effect runs out, eat another one until it's knocked out, also, note that eating a rare flower will make the Tapejara agro on you, but not just you, also most wild life around you.

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