This game is unique. There has never been a game similar to this one.
Yes, it follows the basic MOBA formula of creeps/towers/"heroes"/loadout builds/base, but past that everything changes.
Mechanically speaking, the game uses a 2D platforming free-side-scrolling approach. You move using the keyboard, and aim/attack using your mouse. Controllers can be used as well, if that's more your style.
There are 4 main maps, each with an entirely different layout. Generally, 2 lanes exist, though most maps have open areas and choke-points.
The "heroes" (nauts) are incredibly different from each other, in terms of abilities and playstyle. There's a chameleon assassin that goes invisible, a russian monkey that flies using a jetpack, a squid that anchors you in place, an overweight viking that hurls you into the air, an all-eating creature that spawns stationary minions, a floating brain that controls a swarm of drones, etc. for a total of 16 nauts, plus an additional 5 in the still growing expansion (the expansion marked a first step towards a continuous development effort, which I mention further ahead, and is not in any way pay-to-win). Each naut has its own learning curve. This makes the game spectacularly varied, as not only are the nauts unique from each other, the 3 naut teams mean there are a huge number of possible combinations, which in turn mean a huge number of approaches to a single match. Not to mention that many nauts can steer their own style in very diverse directions depending on which items they go for in their build.
Last, but not least, the game is fun
. As the intro makes quite clear, the underlying design theme surrounding the game is not fantasy or sci-fi, but instead a sort of nostalgic-childhood-saturday-morning-cartoon-fun
Competitive? Yes. But also a game in which you can kill a flying monkey by having a fat viking throw an exploding gnome at its face.
It is also essential to point out that the developers are still very much working on the game. Yes, it was released back in 2012, but it has evolved immensely throughout the past three years. As you will find if you snoop around the game's website, the developers, who frequently post in the forums, intend to keep working and adding features to the game, while polishing and improving the ones already present. This is a project with long-term goals, and the players are having a blast watching the game grow and having their feedback taken seriously. (this is not early access in any way)
All in all, a very fun game, with a great community, a unique design, and surprising strategic and tactical complexity.
Grab it. Play it. Love it.
tl;dr: fun, unique, surprisingly complex