Cid and Nero found a way to combine Alexander's temporal displacement and Omega's ability to travel the rift to send the Crystal Tower to the First. The final boss of The Twinning dungeon is an artificial Alexander that the Ironworks built.
Not sure how to quote someone on lists so thank you for answering. The Alexander story is important to the MSQ. It's literally the answer to "how the fuck did you even manage all of this?". As often said by the devs all of the alliance raids are important.