5. Multiplayer
The multiplayer was the surprising hit of Mass Effect 3. Many players initially discounted it, thinking it would be slapped on and worthless. And boy, were we wrong. It continually keeps me coming back thanks to the wonderful maps and great level of customisation. And all. Those. Unlocks. There are so many new characters, weapons, powers, and appearance items that even after so many hours, I've barely scratched the surface. There is so much to do here, and all of it is thoroughly enjoyable. What's most impressive is how the depth never drowns you. It's highly uncommon for a studio to get their first multiplayer right. Uncharted 2's online was fun, but lacked many advanced options so the player base got bored. Uncharted 3, however, threw in a lot of stupid and pointless options that made the game just a mess to play. Conversely, ME3 just gets it so right.