A true gem in the sea of 90's Playstation games.
First off, a quick summary of the game. It is a 2D side-scrolling platformer (created by Doug TenNapel, the man behind Earthworm Jim) in which you play as Klayman trying to defeat Klogg (from the prequel The Neverhood), who has taken over the SkullMonkey's planet and enslaved them into building a machine to destroy the Neverhood. All of the environments and characters are sculpted out of clay (including the cut scenes). So, that's basically it. Now, on to specifics.
As I previously mentioned, the entire game is sculpted out of clay. The character sprites, levels, items, etc. This gives the game a unique feel that you just don't get with many other games; it's like you're playing through a dream, almost. All of the clay level designs are wacky and inventive, not to mention beautiful, so every stage you get to feels unique in its own way. Also, seeing the character's movements done in claymation is just plain cool. In addition to that, the character design is just insane (but really neat). For example, the second boss you face in the game is Joe Head Joe, a giant head (actually just a picture of one of the game artists) with arms and legs attached to it who spits fireballs and whose eyeballs pop out and bounce around (they regenerate). I should also mention that in between worlds are cut scenes done in clay stop motion animation; they're packed with humour and creativity. It definitely makes you feel like the game designers should make a feature length film (it'd put Nightmare Before Christmas to the test). By and large, SkullMonkey's graphics are terrific.
In terms of game play, SkullMonkeys plays like your typical 2D platformer. Run forward, jump on enemies heads, fight a boss. But yet, when you play this game it feels like more than that. I don't know, it may just be me. There is one slight problem (which is why I gave it a 9 in game play); sometimes the controls feel a bit loose, so when you're jumping, the game tends to have differing degrees of response. Also, the method of vanquishing some enemies aside from butt-bouncing is unclear at times; there are parts where you'll walk right into an enemy and he'll die, and other times when you'll die trying to jump on their heads. In general, though, these are minor problems. It is also pretty darn difficult after the first six or so worlds, but overall just right (although I lost about 50 lives trying to beat the last level).
What really does it for me is in the sound department, where SkullMonkeys really excels. It has arguably one of the greatest soundtracks made for a game. The music is honestly just great, and that's really all I can say because it's indescribable in terms of genre or whatever. So much so, that sometimes I found myself clearing an area of enemies just to sit back and enjoy the tunes. One great example would be the "Bonus Room" song that plays while in the bonus stage. It consists of a gentle acoustic track while a lullabyish voice sings (like a pedophile). The sound effects are nice too, if a bit shallow at times. The squishy clay noises, whooping skullmonkeys, and yodeling (in the snow level) add nicely to the atmosphere.
Overall, SkullMonkeys is an amazing (and overlooked) game that I strongly recommend to anyone. It's definitely something you don't want to pass up. A true gem that deserves to be remembered always as a work of art and a fantastic and truly unique video game.