Mass Effect is one of those games you'll never forget -- it has spectacular visuals, great gameplay, and a great story.
Mass Effect is set somewhere about 200 years in the future in a huge and great and quite diverse universe. It will place you in a huge galactic danger of being conquered by a legendary agent gone rogue who's leading an alien sentients known as the Geth to destroy the universe. You'll start off creating a character, you could use the standard Shephard, or create your own character and choose his or her background. Whether it's that your family was killed off or you followed your families footsteps in the Alliance military. You're the best soldier in the Alliance military. You'll end up on a advanced human ship, known as the Normandy, and you'll be put on your first assignment on a human colony known as Edon Prime.
Since I don't want to spoil anything, I won't go any further on the story. The gameplay is superb for a RPG. When you create your character, you get to choose the class you want to be. Whether it's a soldier or a biotic or a engineer. Now, you may think it's a action-adventure or a shooter based on first glipses when you see the class "Soldier" in action. But this RPG is definitely a RPG through and through. What class you'll choose will play throughout the game very differently. It's a whole new thing, it's hard to get used to but after sme practice you'll be good in no time.
I'm not really a RPG gamer, and never really been interested in RPG games either, so this is my second RPG that I've ever played with Oblivion being my first. So I didn't know exactly what to expect. In the visuals department, it's absolutely superb, better than mostly every game out there. Since the game does use teh Unreal engine, you'll get some popping in and some minor framerate issues during loading and auto-saving. Overall, everything looks absolutely amazing. The planets and areas you can explore are all different and are very exciting to explore save a few frusterating planets/moons.
Where Mass Effect truly stands out is the music and sound design. It has an unprecedented amount of top-notch voice work with thousands of voice commands. This is one of the rare games where it seemed as though you will truly play a role and feel the impact of your decisions. Do you want to be the good guy or the renegade? The score is amazing and may sometimes in some areas give you a slight chill due to the dramatic tone of the music.
Overall, this is a RPG that people will be playing for years to come and will be talking about until a new Mass Effect game is released. Bioware really outdone itself here, it's RPG elements are second to none. If you own a Xbox 360, this is a must have game.