CapCom Unity has details on a DLC pack coming on Thursday to Umbrella Corps to add Spencer Mansion from the original Resident Evil to the game. Here's their outline of what this will bring:

Attention all the battle-hardened mercenaries climbing the online ranks of Umbrella Corps: a new zombie-filled warzone is on the horizon. Players will be able to return to the infamous Spencer Mansion from the original Resident Evil to engage in fast-paced, 3-on-3 battles via free DLC coming later this week.

The iconic Mansion may have been blown to smithereens at the end of the first RE, but this nostalgic DLC pack lets players step through the ornate halls and corridors once again. Use your memory of the Mansion’s unique layout to your advantage as your pursue and ambush enemy combatants with your lethal Brainer axe weapon. Take cover behind the statue that once housed the useful map of the Mansion’s 1st floor, or wage war in the deserted west wing dining room. Of course, you’ll want to beware of the zombified Umbrella researchers roaming the halls as well as enemy players.