The original Assassin's Creed was slated to offer multiplayer options for online play, but it was ultimately cut from the game and wouldn't be introduced into the series until several years and iterations later. Assassin's Creed Brotherhood was the first in the series to offer competitive multiplayer, and 2014's Unity brought co-op gameplay into the mix.
Former Ubisoft technical director Julien Merceron revealed that the studio had originally played around with implementing a multiplayer mode into Assassin's Creed at some point in the game's development but ended up scrapping it for reasons he did not get into.
He revealed that some players who had plugged in a second controller into the game while playing it on the console managed to discover some of that early code through a bug. In doing so, players would spawn a second Assassin to run around in-game.
Merceron does not know if the bug was patched out, but he said that the team developing the game did not give the mode any testing or polish because they thought it was disabled.
Merceron, who now works for Bandai Namco, departed Ubisoft after shipping Assassin's Creed to work at Square Enix and later Konami.
Multiplayer is noticeably absent from this year's iteration, Syndicate. Ubisoft says it intended to return the series to its roots by focusing entirely on the single-player experience.
via GameSpot.