The concept of Eversion, on the surface, is much like Mario. You run across the screen, jumping on enemies and collecting coins (or gems, in this case). There are 240 gems throughout all the levels, and once you collect a gem, it is yours forever. Not only that, but there is no lives system: dying will merely reset you to the last checkpoint. You won't even lose the gems you had collected! It's a very forgiving system, but you will definitely need it

Where Eversion differs from classic platformer gameplay in a big way is in the puzzle aspect. There are certain areas that cause bits of music to overlap with each other and the sky's color to change a little. By pressing X in these locations, you shift between worlds, represented up at the top right. For example, you can be in World 1-1, but when you cross-over, you are now in World 1-2. The basic landscape is the same, but there are some key things that shifting between worlds changes. These are:

• The solidity of clouds and plants. Each world has a different solidity for these different items. For example, in World X-1, clouds are pass-through, where plants are not.
• The nature of the enemies. As the worlds get higher, enemies slowly get more and more lethargic, until they finally just lay around. In contrast, if you continue after that point, enemies become quick and gain a bloodthirsty appearance.
• The visuals. In higher-numbered worlds, the landscape becomes more and more hellish, with grasping demonic arms, floating skulls, and copious amounts of gore whenever you die. There is also a change to the end screen, saying things like "Give up"
• The effect of brick blocks. In lower levels, you can't harm them or you have to break them by jumping from beneath. In higher levels, they break simply by you touching them.

The puzzles and such are not particularly hard, but may take one or more tries to get down just right. The real draw to Eversion is the amount of detail that was put in to scare the player. This isn't a game that relies on cheap surprise tactics. Things become more and more bleak and hellish as you progress, and the music changes from happy to menacing and then goes away completely. All you hear is your heartbeat. This combination of graphics and audio devolution will definitely send shivers up your spine.

Eversion is not a game with a whole lot of replayability. There's no extra content, and no level editor. However, what you play will definitely haunt you for a while, and if you want a good game that gets progressively creepier and more challenging, you'll be hard pressed to find a better game than Eversion. You can download the full game from the developer's website. Windows only!

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