Really the easiest way to steal the eggs is to grab a pteranodon, and get the deinonychuses aggroed on you, and you get them to chase you either off a cliff or aggro it onto another wild dino, then take the egg. If you dont have those options you could wait till the deinos wander away from the egg or kill them yourself. (theyre pretty easy to kill with a high level pteranodon as long as its not a huge pack)

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