Midoriya, Bakugou and Todoroki fight a villain with a prophecy quirk, but actually it's a greek prophet from the PJO universe that some how got to the MHA universe, the prophet tell them a prophecy and at the same time, Rachel at camp half-blood is giving the same prophecy. Before they know what's happening and what the villain is saying, they get sucked into a portal and appear in the camp, surrounded by demigods. I do not own anything PJO or MHA related.