More races of the galaxy are represented in the team than were in the first Mass Effect, and through the companion stories the surrounding world is expanded. Unfortunately the encyclopaedia from the first game still exists and is utilised as a crutch by the writers – however it's unnecessary to actually consult it, as all the information that the player needs is conveyed by the companions.

Technically, the sequel has not made any notable changes. To this day, the game still looks and sounds good, though it is fairly obvious that the levels are small and the obvious waist-high walls are always a clear signpost that combat is about to start.

Which brings me to Mass Effect 2's big change: mechanically, the game has been turned into a cover shooter, similar to Gears of War. It's a puzzling change as mechanically there was nothing wrong in the combat of the original. It doesn't work too well with the special powers either, as aiming them is somewhat cumbersome with this new stiff camera.

To further reinforce the similarities to shooters, gone is the overheating mechanism – we're back to the safety of magazine reloads. Naturally, this change required a nonsensical retcon of existing lore and it really serves no purpose, as bullets are so liberally spread around that there is absolutely no danger of ever running dry, not even if you are a soldier and thus use guns for every encounter.

The special abilities of various classes and their skill trees have also been overhauled. They weren't that interesting in the original and now they are largely meaningless. Every encounter is possible to complete with any squad composition as your teammates are largely useless, thus levels had to be designed to accommodate every class that Shepard could be – a similar issue that plagued Neverwinter Nights.