Games about evolution, can they work in a non-RPG (SoulBlazer series) form?
The awnser is yes, yes they can. In EVO you start out as a little fish, trying to survive, but as you defeat and eat other creatures, you gain points. With the points you can make a part of yourself evolve, slowly you'll little fish will turn into a a small shark. But don't think it ends after that, after the fish part, the rest of the game takes place on land, and slowly change into a bigger and stronger creature.
The gameplay of EVO is quite simply, eat or get killed, you have to eat to evolve, or else you'll grow weak, think of it as a level-up system. You can make your creatures look weird and freaky, or just try and get real creatures by choosing parts of the same animal. The main flaw of EVO is that it's short, really really short, and can easily be beated in a couple of hours, unless you try and become the strongest creature in every part of the game.
EVO is a fun little game, and should be checked by people who like games that are... different then the rest.