Fun, addictive but also frustrating.
At its core Gotham City Impostors is similar to Team Fortress 2 in that you can pay real money for funny hats, with the difference being the factions. Here you can dress up as either a wannabe Joker or Batman, hence the "Impostors" title. The gameplay is immediately gripping and will keep you playing for hours despite the small selection of levels and the sad fact that noone is playing anything except team deathmatch. You can costumize your player character with a variety of clothing options which you can buy with ingame money or real $$$. The costume packs are definitely overpriced and it takes forever to earn enough costume coins in game which is not a big issue because the game is just plain fun. The learning curve is steep but you'll get into the game quite easily if you have literally played any fps since and including wolfenstein 3D, with enough nuances to keep you playing and improving your skills to annoy the hell out of the opposing team with your sniping skills. Slicing your way through enemies with a Katana while on rollerblades never gets old.
What sets Gotham City Impostors apart from other games in the genre is the selection of gadgets and modifiable weapons inspired by the Comic Universe, anything can be improved by a jetpack and bouncing boots. Nothing here is entirely unique but it's different enough to have a distinct comedic flavor that you won't find in the fps circus of brown that insists on staying in town, drinking all the beer and farting in the elevator.
Wherever there's light there is shadow and while the roaches lurking in the darkness all wear silly hats they remain a nuisance. Most of the levels have the weakness of what can be referred to as clusterf*ck-points. Every player piles in on one place and it's far too easy for a team to overpower the other because players will keep spawning in that exact area. This happens quite often due to the design and small size of the maps. Their colourful charme helps to alleviate this problem most of the time, but expect to repeatedly get angry.
The main frustration comes with the limited nature of Gotham City Impostors. Few costume options, few levels, few useful weapons, only two factions. A lot of potential is left untapped. Imagine what this game could be with a sandbox approach, several different factions fighting for a piece of gotham city - think impostors of batman, joker, penguin, catwoman, twoface etc. each with their own unique traits, design, weapons and gadgets and you'd have an incredible game.
What we have so far is definitely fun and I recommend playing it while it's still alive, but I see it more as a proof of concept than a finished game.