As detailed by the Ubi Blog, the collaboration came about after an informal meeting nearly three years ago between the Assassin's Creed and Final Fantasy development teams. In the leadup to today's announcements, the two teams seeded Easter eggs into trailers for their respective games, including the Final Fantasy XV Omen trailer, this year's Assassin's Creed Origins announcement trailer, and the Origins Gamescom trailer.
The partnership also debuted with a new piece of artwork featuring Origins' Bayek and Final Fantasy XV's Noctis, which was available for attendees at Gamescom 2017.
Assassin's Creed Origins is currently the subject of this month's IGN First reveals — stay tuned to our Origins First hub for all of the latest reveals and gameplay videos. And for those looking to secure a copy of the game before its packed October 27 release, check out IGN's Assassin's Creed Origins preorder guide.
IGN also had a chance to dive deep into Origins' recreation of Memphis at Gamescom 2017. This isn't the first time Assassin's Creed has appeared in a Final Fantasy game — Ezio Auditore's outfit appeared in Final Fantasy XIII-2, which was one of several cross-brand collaborations for the FFXIII era of the franchise.
At Gamescom, Final Fantasy XV's director told IGN that the recently announced mobile version of the game has "a chance" of coming to the Nintendo Switch.
For more from the convention, stay tuned to IGN's Gamescom hub for all of the latest news, previews, and more. Jonathon Dornbush is an Associate Editor for IGN. Find him on Twitter @jmdornbush.