If you're going to sit down with some friends and play a fighting game, this isn't the one.
While Battle Monsters does have some good ideas and twists on the standard fighting game, the whole package is poorly executed, and comes out looking like a Way of the Warrior rip-off.
The characters in Battle Monsters are badly digitized, look fuzzy, and don't animate well. They're also fairly non-descript, with the exception of a headless giant who carries his head in his hand, and a pair of twins who fight as one. The backgrounds are multi-leveled, with platforms that fighters can jump to, then continue the fight on. But controlling each Battle Monster is a chore: Two attack buttons and two different types of jumps serve to create both a lack of variety and loads of confusion. The only good feature in the gameplay is the ability to send your opponent skyward, then hit him again while he is still airborne. This leads to eight or nine hit corner combos, and the only real bit of fun in the game.
Battle Monsters' sound is surprisingly decent for an otherwise lackluster game. The hits and screams are as good as most fighting games (someone must have stayed up late smacking sides of beef with boat oars for this one). The music is decidedly warlike, and will no doubt infuse violent urges into many players' bloodstreams. Both the sound and music stick out as the some of the only passable parts of the game.
Battle Monsters is a pathetic two-player game, but as a one-player game it does provide some entertainment. If you're going to sit down with some friends and play a fighting game, this isn't the one: many fighting games out there are much better. But if you're bored and lonely, and feel the need to beat up a headless guy, Battle Monsters might keep you occupied for five or ten minutes.