I think it's rather sad this game hasn't been so well noticed; because it's really worth playing. If you like monster mashes, this is actually better than Rampage (!). And yes, it probably is also better than Godzilla Unleashed. For starters, this is a beat em up game. BUT you can walk free in cities, and face opponents (player 2, for example), and fight them, crash buildings, terrorize humans. You can fight as Congar, the gigantic Chimpanzee; who's like a bigger King Kong, and brown. You can fight as Togera, which reminds of Godzilla, but he can get spikes out of his body. And I must mention Agamo, the giant statue monster from some kind of cannibal island, I think. He can take of his head, make it bigger, grow a new one, and hit his enemies with the bigger head. THAT'S bad-ass. And we got Magmo, the lava monster; Ultra-V, the Japanese robot; Zorgulon, the giant brain-alien; Kineticlops, the big eye with a electric body, etc... And they are all unique to fight with. Also, there are characters with flying abilities. Only 2, though... Preytor, the mantis; and Raptros, the dragon. There also is a "story mode", called Adventure. You fight through levels there, and meet some unique and cool bosses. If you play with someone else, there's also 3 fun mini games. And this is the downside of the game - it gets boring if you play alone. After you complete the story mode with all the characters, you won't play this again if you don't have a friend to play with. It's kinda like Super Smash Brothers.
But I think this game deserves to be played. If you can find it somehow, got a PS2, and you love monster mashes, you really should buy it.