First off all:
(Nice singleplayer and GREAT multiplayer with bots and 4 player (that makes a 14 player multiplayer)!!! Really good!
Get timesplitters: Future perfect .
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
then buy timesplitters 2
some other great NGC-games:
1) tales of symphonia: VERY VERY GOOD! Best of the tales series.
2) Eternal darkness: Sanities requime (Nice pseudo-horror).
3) Metroid 1/2 (Best shooter/action adventure, only strange controlls
).
4) Resident evil 4(!!!) And maybe 0.
5) Chibi robo... kinda fun
...
6) Ikaruga (fast passed 2D shooter with 3D graphics)...
7) Baten kaitos 1/2 (Iff u like card based fighting systems).
8) Soul caliber II (Link is in that game so BUY IT
).
9) Vieuwtiful joe 1 & 2 (Nice quasi, cell-shaded graphics)...
10) Killer 7... (Again, iff u like quasi, cell-shaded graphics, it also has some heavy political stuff in it)...
11) Metal gear solid 2 The twin snakes.
12 Beyond good and evil (Really, really good game with the caliber of the Zelda franchise, too bad they didn't make a sequel because of low sales)
And eerhm, the rest of the games u already own :D
And get zelda: Twilight princess, if u have a wii; get it on that console!
*'Actually there are many great games on Gamecube, even some 3th party efforts are REALLY REALLY GOOD'