Although it is challenging, anyone looking for a simple and fun acrade game should give Gauntlet a look.
The graphics, well they're acrade grahpics but they are good enough. You can easily tell the difference between the different characters and there are a variety of monsters as well. Some levels will look similar sometimes but they all have some differences.
The gameplay is button-mashing, you'll only use 2 buttons while playing, the A button and the analog stick. As I said above you fight off hundreds of monsters looking for the exit to the level. There are a 100 levels and they get harder as you get higher. I've only gotten up to level 19 up to this point and it is very, very hard. You need to make sure you watch your health as well, not only does it decrease slowly overtime but the eniemies can drain your health pretty fast if your not careful. There are 2 game types, single player and online play. The single player isn't too hard since you can increase your health by around 500-700 points by pressing the Y button. Do this a few times before you start so you don't have to worry about your health. Unfortuantly you can't save so if your looking to get the achievement points for reaching level 100 you better set aside a day for it. The online play can support up 4 players as stated above and you can get achievement points for getting to higher levels and doing other things.
Overall, its a decent title that can be enjoyable especially if your playing with friends. I'd recommend it to anyone who has Mircosoft points to spare since its only 400.