- Fire Emblem: Path Of Radiance

- Resident Evil 4

- Metroid Prime

- Tales Of Symphonia

- Legend Of Zelda: The Wind Waker

- Super Mario Strikers

-Resident Evil RM

-Resident Evil 0

- Star Wars: Rogue Squadron II – Rogue Leader

- Viewtiful Joe

- Gladius

- Animal Crossing

Oh my goodness. The struggle was real. Not for the usual reasons either. I had to include Animal Crossing....and although I did enjoy it at the time for being such an oddball experience, I played for only a small fraction of the time I did on the GC when I mistakenly bought the DS version. It's enduring popularity is....whatever. I was also well and truly finished with both the Mario Kart and Smash Bros. franchises by the time the GC came out. I didn't even bother trying them, much less purchase. Another reason why this list was kinda difficult to make, was that I played most of the good 3rd party GC content on the X-Box, because they were always at least a bit better on that platform, and sometimes, markedly so. Then there were The Dreamcast games that I had already played. On the Dreamcast. A very lovely addition for some, but to me, meaningless.

It was an enlightening revisitation. In making this list, I have come to the conclusion that the GC is the least favorite console I've ever owned. Yet, still a pretty good system overall.

Where's Phantasy Star Online?  

I picked up reasonably cheap on Steam awhile back on a sale. So if you have PC probably can pick it up there for like 4 or 5 dollars during a sale.

Apparently I gotten worse but the game is all about memorization and quick skills like knowing when to change colors.  The more you play usually further you get.  However I've had friends that are good at other genres play it and they are terrible.  Funny how some people can be good at genres but then you play another genre and they suck.  It's like how you are that bad at Smash?

In no particular order:

F-Zero GX
Luigi's Mansion
Zelda: WW
Zelda: TP
Smash Bros. Melee
Zelda: Four Swords Adventures
Sonic Adventure 2 Battle
WarioWareInc. Mega Party Games
Metroid Prime
GoldenEye Rogue Agent
SSX 3
Super Monkey Ball 2

It's cheap as dirt here in the US too. I'll definitely pick it up, then!

In no particular order:
-Tales of Symphonia
-Super Smash Bros. Melee
-Phantasy Star Online
-Mario Kart: Double Dash
-Gladius
-Super Mario Strikers (Only with 4 players)
-TimeSplitters 2 and 3
-Guitar Hero-games
-Conflict: Desert Storm

To me, the Gamecube will always be the multiplayer-console, as I never owned the console myself, but we used to play it at my friends house all the time, so any game with a proper local multiplayer was always in rotation.

Strange choice of 12... were you planning a top 10, but when you couldn't remove 2 you loved from the list you decided to make it a top 12?

Too many to choose from...

Gladius is another one I've heard good things about but need to try. 

It's really good, and sadly often forgotten. It's especially great when played in co-op, with every player controlling their own characters in battle and working together.