I’m at the T-Rex boss fight and I used the egg to stun him and then used the second egg to damage him. One of the eggs is gone now as he destroyed the bird that dropped it. How am I supposed to make him expose his weak spot without the second egg?
You need to use Gooigi. Stand near the egg and activate Gooigi. Run over to the T-Rex and he will start to eat Gooigi. Once he is chewing, switch back and you will be able to shoot the egg at him now that the weak spot is exposed.