Mass Effect 3's multiplayer mode will be expanded via an upcoming DLC pack, a leaked image suggests.

The screenshot shows a mysterious multiplayer unlock-pack stuffed with half-a-dozen new classes.

Fresh character types include a Geth Engineer, Geth Infiltrator, Batarian Soldier, Batarian Sentinel, Krogan Battlemaster and Asari Justicar.

The Geth and Batarians are entirely new races to the multiplayer, while Battlemaster and Justicar are fresh class types.

The pack is currently "test DLC", according to the gamer who snapped the image and promptly posted it on his Facebook profile (later picked up by Reddit).

Unlocked via the game's "developer server", the DLC was then downloadable from Mass Effect 3's multiplayer store, just like standard multiplayer unlock packs.

No pricing options or release plans were mentioned for the pack, which would be the first slice of extra content for Mass Effect 3 since controversial single-player DLC From Ashes.