Best mount to use would be pteranodon because they r very fast flyers. Find a nest and lure deinonychus far away by letting them aggro to u then fly slowly away from nest and they will follow you Get a preferred distance away from the nest then sprint far from them so they aren’t going to follow you. Then circle around back to the nest. If it takes too long to get back to the nest, new deinonychus may have wandered there so you might have to repeat the process, but if not, quickly dismount, grab the egg, then fly out very fast. U can also lure some allos in there because nearby deinonychus will attack it and they will be distracted

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