The only thing it really succeeds in is being a 'god-awful' game.
Let's talk about the game itself: gore and sex. There, all done talking about the game itself. Simply put, there's nothing to except mash the square button and watch as everybody around Kratos spurts more blood than there is in ten whales put together. In fact, the game is so pathetically easy on the hardest difficulty that the real difficult thing is not getting up after ten minutes and going outside to confirm that the real world is still a beautiful place and it's all in your head.
There is no real plot at all, since all Kratos does is kill people and shout: "You lied to me! You betrayed me!" but it's pretty easy to deduce what's happening from the monotonous gameplay itself: Kratos is a bald sex-fiend who is hankering after the Hapless Jerk of the Year award, and he kills everyone he sees just because he has no life, including his mother, who turns into a monster for no reason except that she wants her momma's boy get the Hapless Jerk of the Year Award.
The gameplay is terrible: monotonous is an understatement. Simply put, the developers made a horrible travesty of the Devil May Cry with one small difference: there are no puzzles and no wicked combo moves, just mashing the square button and watching people die bloody deaths. There is one single puzzle though: how in the heck did they make a Devil May Cry-esque game boring? The developers managed. In fact, calling the game Devil May Cry-esque is an insult to Capcom's superior series.
The music is just awful. It's just the 'aah-ing' of a choir for the whole game's music, and the sooner you come to accept that this game is better played with the volume on zero, the better. The voice acting is even worse. The only thing that doesn't repeat itself like a bent record is the protagonist Kratos, and in case you're wondering: yes, he does suck.
The graphics are abysmal. The game allegedly uses all of the PSP's 333 MHz processor to make visuals more realistic, but it completely fails in making them not stinging for the eye to look at, and Bubsy for the PS1 has better graphics than Ghost of Sparta. The graphics are a whole new levvel of ugly that surpasses ugly, mugly, bugly, fugly and truggly.
The game is also full of thousands of bugs like hardness errors, prolonged animations and shifting textures, and coupled with awful everything else, this makes it the worst ever PSP game.
In conclusion, the developers relied a hundred times more on gore and sex than they did on anything to make the game enjoyable, and all in all it's not only the worst ever PSP game, but the worst game ever besides Big Rigs: Over the Road Racing.
It gets a 1.0 simply out of shock for it being so awfully awful, and for the reaction you'll get if you have your younger siblings (of which I have none, luckily) watch while you play which will definitely involve them imploding your face with a hobnail boot.
Ghost Rider for the PSP is gold compared to this trash. All in all, I don't think anyone can play through this game more than once without spontaneously combusting. I think the universe makes sure of that.