This game feels like a mix between Super Smash Bros. (particularly Melee) and the 8-bit Kid Icarus as far as gameplay and singleplayer campaign goes. Each part is more noticable depending on whether you're playing multiplayer or campaign. And, let it be known, this was the game that, alongside Bombsquad, led me to purchasing an Ouya.
It's upgraded appearance on the PS4 and on Steam are very much welcomed by me, though I have some qualms for the Steam version.
The PC is, unless you hook it up to the TV, not built for local multiplayer couch parties in mind. Overall, the PC mainly focuses on online multiplayer with the likes of Quake, TF2, and League of Legends. Towerfall does not have online multiplayer, and though arguments have been made supporting its non-support (and I agree with most of them), you essentially have to get things hooked up and working properly to get a decent couch multiplayer experience with Towerfall. Best thing I will say is that the Singleplayer is a bit easier on the PC.
Because, in my opinion, playing Towerfall with friends on the couch is THE best way to play it, I vastly prefer the Ouya and PS4 versions to the PC version. And, aside from these minor qualms, I think that Towerfall is one of the better combat-platformer (combatformer?) games on the market, outside of Super Smash Bros. itself. If you do not have a PS4 and want to play your PS4 game with friends, Towerfall alone is a solid reason to buy one, though at this point it's somewhat difficult to truly recommend it (hard to say with all these games getting delayed), but if you don't have one and do not intend to buy PS4 or Ouya, get it on Steam. If you have an Ouya, you need Towerfall. If you have a PS4, I will instantly recommend Towerfall Ascension. It's that good of a combatformer game.
Pros: VERY Solid gameplay, neat character design (My favorite's the Thief), a unique concept that by all means may be a steep learning curve (1-hit KO on most attacks) but ends up being easy to pick up anyway. Great soundtrack, and interesting take on the pixel art aspect.
Cons: If you're not familiar with the game, you may get steamrolled by other experienced players. The music, while still great, can get repetitive in the campaign. PC version is, by design of PC, hard to get that multiplayer experience without online multiplayer built-in (which is why I recommend the PS4 and Ouya versions over the PC version, at least for now). Ouya version was what got me hooked on Towerfall, but last I checked did not get the Ascension version that PS4 and PC had.
Overall: 9.5/10 for PC and Ouya, 10/10 for PS4.