The biggest bombshell that BioWare dropped about the story was the fact that Shepard may not survive the second Mass Effect game - and not just for a "Game Over" screen. There will be legitimate endings to Mass Effect 2 that end in the death of Commander Shepard.
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To keep this as part of a usable strategy, players can now use the command menu to issue commands to both allies and Shepard simultaneously. On top of that, Shepard and allies can cripple their enemies by dealing damage to individual body parts, preventing them from wielding weapons, moving quickly, or using their brains as they become bloodied messes on the floor.
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There will be a new exploration system for new planets, so players won't have to spend eternity inside the Mako with this iteration of the series. BioWare will have downloadable content available for Mass Effect 2 and the game will be playable after the credits roll.​