Great idea, average game.
GAMEPLAY: The solo player is pretty fun but can be a bore after finishing(which can be pretty fast). You basicly go threw different zones consisting of your favorite Sega characters. In Sonic the Hedgehog you'll go aorund collecting rings off the court, like you would in any Sonic game, and try to dodge flying missles Dr. Eggman hits at you. In Virtua Cops you'll take out some dudes by aiming and spikeing your tennis balls into there faces without hitting any civilians. This by far is my favorite zone. The thing that becomes annoying is when you actually have to play a tennis match... This sounds a little sad since it is supposed to be a tennis game, but the tennis is the worst part! Overall the solo mode will bore you after awhile. The multi player is fun you can spend hours with your friends. You can nail some zombies, tag some streets, shoot some cops with tennis balls. and even just play each other. The down side to playing eachother is that your tennis games will end up by hitting the ball to the opposite side of the court have your opponent run and hit it to the other side of the court. This will continue untill one player just can't reach the ball any more. So this will make you not even want to play the actuall tennis at all! But along with what I said earlier, there are little mini games you can play with your friends. These are alot more fun to play and makes this game at least some what decent.
CHARACTERS: This part of the game is pretty week. Half of the characters you wont even know if you aren't an old school gamer, but you can enjoy your no brainers like Sonic, and Aiai.
OVERALL: An okay game...the tennis part could use osme shaping up.