If you are alone, ride a pteranodon. This is because they cannot latch onto a pteranodon, but they can latch onto an argentavis. Lead the deinonychuses away from the nest and into a group of brontosauruses. Agro the brontos and make them hit the deinonychuses, and then watch carnage ensue. Rinse and repeat until the deinonychuses have all died, make sure brontos aren't agroed and then safely snatch the eggs from the nests. Using a whip is an optional choice to make things run smoother and faster. After this process, go somewhere else for a few minutes and come back to do it again. With very little practice, this can be a very effective method.

If there are no brontos in the area, use the pteranodon as a weapon. Swoop in and twirl into the deinonychuses until they die. WATCH OUT for raptors. They WILL dismount you in a heartbeat, whether they were targetting you beforehand or not. After the deinonychuses are dead, swoop in and snatch the eggs before leaving and repeating the process.

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