Called the Squad Leader trailer, it shows intense combat going down between Cerberus and Commander Shepard, Garrus, and Liara. A few things can be gleaned from it, mainly that the powers appear mostly unchanged in Mass Effect 3
from their Mass Effect 2
forms. Shepard clearly casts Incinerate at one point (combined with the sniping, you can assume this trailer shows Shepard as an Infiltrator), also Garrus seems to use Concussive Shot later on, while Liara cast Singularity and all look exactly like they did in Mass Effect 2
. Finally it looks like the cute little disc grenades from Mass Effect 1
are returning. Here's hoping the keep their flat tragectory as well. It made aiming them a snap, and nothing can ruin grenades faster than not being able to toss them accurately.