You get it it seems fun at first. It's not. You can do story mode (which is pointless), mega challenge (really dumb),melee (gets boring), and training (do it once and then it's useless. I definitely reccomend to never buy or rent this game! The only thing good about it is the title screen music. The graphics are horrible. Buy the gamecube version, it's a blast.
I actually own this one. This was the second DS game I had bought, and was seriously dissapointed. It starts out quite fun. Above average, actually. And perhaps if Single-Card Multiplayer had been added, it would have been a worthwhile product. Not such. The story mode is rediculously short and should hardly be considered a story. You have simple controls. One for light punch, one for strong punch, one for special, jumping, guarding, rolling, and you can use the Touch Screen to use one of the three items you picked up. Sounds like a good deal of fun, and it is for a day or two, but don't buy it like I did. I was unaware and it was one of the few fighters for the DS out. And I was being naive and wanted to get something with my money THAT day. And my only other choice was Star Wars III for DS. The only reason I would even consider renting this is to play multiplayer with somebody else, which is the only way I could squeeze and ounce of enjoyment out of it. Even then, its quite buggy and whoever gets the first hit has the advantage.
So, if you own this yourself and know somebody else with a DS, consider renting it. Otherwise, no. Do not rent. Its a waste of time and completely not worth it.
It was pretty fun when I first stared playing. After I beat it with everyone I realized there isn't much else to do. it was a cool idea to unlock outfits and pictures and things like that, but there should have been more content as far as game play goes. the fighting system is good, but it did start to seem simplistic after a little while. it's a good game for the kids, but i wouldn't recommend it for people older than ten years old. But that's just my opinion...