I have had a GBA for years and only really had a few games actually! I feel it's a perfect platform for side scrollers, what are some of your gems on this?
The only ones I've ever had were the Sonic Advance games and DKC. Both are pretty good, though DKC is better on the SNES.
Sonic Advance was a fantastic series Like wow was it a fun time. And then throw in communication with the Adventure titles on the Gamecube which was completely out of nowhere.
The Super Mario Advance series were awesome. Basically, just ports from SNES's Mario all stars games, but they are perfect to play on a handheld like the gba.
Alien Hominid was a top game, CT Special Forces Series and Lilo & Stitch are also great side scrolling run and gun games. Ninja Cop too although that isn't entirely a side scroller. Pretty much platforming perfection though.
I also recommend Sonic Advance. Unlike Super Mario Advance games, Sonic advance takes advantage of the GBA processing power. One of the results is tons of frames of animation, which really brings the game to life. I haven't played it yet, but I heard the Metroid game(s) was really good too.
Obviously the GBA has a blast processing chip in it. Metroid Fusion is really good, I enjoyed it when I first had a GBA.
It has teh 32X POWER right in the gmaeboy! Edit: Oh, I guess I should mention Super Mario Bros 2 (Famicom mini). Widescreen version of a damn hard classic, plus it's all funky and yellow and the box is super cool.
Besides the ones already mentioned, I would also recommend: Kirby: Nightmare in Dream Land (which is actually a remake of Kirby's Adventure), Yoshi's Island, Super Mario Bros. (NES classics), and Castlevania: Aria of Sorrow.
I always mention this but the first Turtles game by Konami is an absolute blast on GBA. Tight controls, lots of moves, lots of variation (every character has a different bonus stage) - just a really good game. Think Konami in peak SNES mode and you will get somewhere close Another really good game on GBA is Drill Dozer. That is loads of fun and a bit different to the norm. GunStar Super Heroes is also absolutely epic with tons of levels and nods to other games and as always the action is fast and frenetic Obvious big name titles worth checking out would include the Castlevania games, Mario titles, Sonic Advance titles, Metroid games etc
Side scrolling isn't really a kind of game. Platform, beat em up, shooter, racing games can be side scroller. So what kind of side scrolling game are you talking about ? I agree with Lemmywinks about Alien Hominid and Ninja cop