EVO (as I will be calling it), is a really odd game. I neglected to try it for quite some time because I thought it was a little ugly and simplistic, and I was quite surprised when I actually did give it a try. The basic idea is that you control a creature and choose changes to make to it as it evolves, making it stronger and more capable as you progress. This premise is a little misleading - it is not a tree based system. Evolution works a lot more like RPG equipment in this game. You can pick a different type of head, a different type of body, etc. etc. but they don't influence further changes (there are some exceptions). It's also a bit aimless. You can't, as I did, try to make a "defence" prioritised creature. Instead you kind of just have to go for everything at once, or you'll be wiped out.
The reason you will be wiped out is because this game is HARD. I don't mean in that glorified super mario kind of way either. I mean more in the unbalanced kind of way. I try not to over-use save states (although I always use them), but this is one of those games where if you have them tempting you, you'll abuse the hell out of them. Alternatively you can waste hours of your time to bad luck. The difficulty is admittedly, only limited to boss fights. It's also very grindy. The main thing you're going to be doing in this game is biting other creatures to death, to get "evo points" and get a better body. At some points in the game you might only get 1-10 evo points form a single enemy, and you need 200+ to upgrade any particular body part. On top of that, hit detection is rubbish. It's a game of being in the right place and biting at the right time so that you don't bite too far forward and take collision damage when the animation finishes or gets cancelled. Very messy. It's actually so messy that I almost can't recommend it.
Almost. It is a very cool game and a nice experience despite the frustration. It's worthwhile if you're into playing janky old games. The thing that really makes it for me is the personality this game has. It's another classic case of a game with simple touches that add together to make it better overall. Once you get past the initial simplistic look of the graphics, they're actually quite nice. There's almost a terrarium kind of feel, and it's definitely better once you're out of the starting area. The animals themselves have personality. Some of them look happy, some of them look really depressed. There's a lot of light humour in the game too, from the dialogue with and between the different species right down to the animals eyes popping when you attack them. With all the things happening between the animals between the ages, it is more like looking into a world than just playing a game. The icing on the cake is that this game has multiple paths and endings. More than I could be bothered trying (save states!!). Do play it if these things sound important to you.