Remaining clues:

11: This game is the second highest new entry to my list and was the first game to introduce multiplayer to its series.

Extra hint: It has a controversial ending... (this should give it away).

My number 10 had so much content cut from it that they made a sequel around it, but the excellence of the game meant that it hardly needed the cut content.

Mass Effect 3.

Super Mario Galaxy?

Extra Hints:

11: This game is the second highest new entry to my list and was the first game to introduce multiplayer to its series.

Extra hint: It has a controversial ending... (this should give it away).

10: An ambitious RPG that was 5+ years in the making but has a controversial sequel that did away with a lot of what made the original so enjoyable.

Extra Hint: This games was the origin of a new franchise.

9: This game has been re-released multiple times and spawned numerous spinoffs.

Extra Hint: Not all the spinoffs are video games.

8: This game introduced a new and popular Nintendo character.

Extra Hint: The main characters are on holiday when the Princess gets kidnapped, and they meet this character for the first time.

7: "Make me feel alive again!"

Extra Hint: Main character's name is David.

6: I did not steal your sweetroll! Why do you have a limp?

Extra Hint: The guy(s) with the limp started a whole new internet meme.

5: This game featured Yvonne Strahovski on the box art.

Extra Hint: This game was criticised for removing RPG elements that were present in the original game.

3: "I never asked for this"... but I can punch through walls now!

Extra Hint: There are 3 games in the series. This is the most recent game and is a prequel.

1: Look at my previous posts. In my first ever VGChartz post I sing its praises. It shouldn't be that difficult to figure out!

Extra Hint: The guy that made Epic Mickey lead the team that made this game.

#11 - Call of Duty. Yes, this high up my list is the very first Call of Duty. It is one of the best first person shooters ever made though. As 'pure' a shooter as Quake or Doom, but with a real character to it. Though this is likely my most played online multiplayer game, it was the single player campaign that made the game shine. A lot of intense levels as you follow the tours of three soldiers during World War II. The game gets very realistic, sometimes you can almost feel the tension and the hardships these soldiers must have endured in real life. Like I said though, this is my most played online game, and can be credited with opening up the internet for me!

#10 - ?
The first game in this franchise of three games (plus expansions) is a cult classic and had sold unexpectedly well. The second game, with it's two expansion packs, is the one I'm searching for, it was better than the first as it ironed out most flaws but couldn't match the first game's sales. When the franchise moved to another publisher though, things started going downhill fast and the game was but a shell of it's former self. Recently, a spin-off was released on an 8th gen handheld under very low metascores.

#10 - ?
The first game in this franchise of three games (plus expansions) is a cult classic and had sold unexpectedly well. The second game, with it's two expansion packs, is the one I'm searching for, it was better than the first as it ironed out most flaws but couldn't match the first game's sales. When the franchise moved to another publisher though, things started going downhill fast and the game was but a shell of it's former self. Recently, a spin-off was released on an 8th gen handheld under very low metascores.