Mass Effect 3 was shown for Wii U during Nintendo's E3 press conference inside a montage of third-party titles. While no one technically announced the title, it proved that earlier reports from the German Facebook page for the game were true. The montage also showed titles such as: Tekken Tag Tournament 2, Aliens: Colonial Marines, Trine 2: Director's Cut, Darksiders II, and Ninja Gaiden 3: Razor's Edge. Videos for these, and more are posted below - except Ninja Gaiden, Tekken, and Aliens.
Wii U - EA - Mass Effect 3 Take Earth Back Trailer
Transformers Prime The Game E3 Trailer
Trine 2: Director's Cut E3 Trailer
Tank! Tank! Tank! E3 Trailer
Darksiders II: Death Lives E3 Trailer
Nintendo 3DS - Warner Bros - LEGO Batman 2: DC Super Heroes Trailer