Kotaku - 've just played a chunk of one of the combat missions in the new Mass Effect 3 DLC, Leviathan. There was a boat. There was water. There was a mech. And Shepard dove to the bottom of the sea, Abyss-style.
Before I got the controller, BioWare's Nick Clifford took us through a cinematic near the start of the DLC. Shepard was aboard the Citadel, interrogating a member of a research team that was looking into something called "The Leviathan," which is a mysterious being apparently capable of killing a Reaper. (I'm also guessing it's quite large, going by the name…)