Considering how Assassin's Creed Unity had work leak before Ubisoft's official announcement, it's only fitting that we seem to have learned about its downloadable content early too. A promotional retail poster teases a pre-order offer for the "Chemical Revolution" DLC.
The poster from Twitter user CriptAssassini (via IGN). Given the setting 18th-century Paris, fans have speculated that the well-dressed man standing with our Assassin is famed chemist Antoine Lavoisier.
The leak of Unity was accompanied by a second rumor, that Ubisoft would release a second Assassin's Creed game this fall for current-gen consoles as well. That piece of the rumor hasn't been confirmed, but given how closely Unity matched up with Ubisoft's reluctant announcement, it seems likely. This DLC rumor is similarly unconfirmed, but an extra mission pack as a pre-order bonus certainly isn't unusual for the series.