It's quite hard to decide. My first ever games were Mario games on the Gameboy Color, and since then i guess I have watched Mario grow. Sonic has speed, and Mario can go inside tubes. Sonic was way more useful. To play Sonic, with all of his cool features, interesting characters and awesome objectives, it's hard to see why it wouldn't beat some of the other Mario games. Most Mario games are based on the same thing: Save Princess Peach. yeah, alright, that is the main point of the storyline, but why not make a series of Mario games that would be more appealing to the player, perhaps by actually saving Peach for once? it's simple. With Sonic, you actually reach objectives and move onto new levels, and face better enemies. Mario has always got those little Goombas in every level. Mario may have better levels, but Sonic has more of a variety of quests, missions, and overall it is probably more fun to play. I like both games, but I think I will be with Sonic. A hard decision.