I don't think any reasonable human being can say that Shank doesn't at least look good. It's animated smoothly and drawn beautifully, with an amazing soundtrack and a huge cast of characters. If Genndy Tartakovsky and Robert Rodriguez's freak baby went on a tequila bender, you would get something that looks like Shank.
I can't quite make up my mind, though, whether it's an ambitious platformer that spent too much time on visuals and music and not enough time smoothing out the gameplay, or if it's just unapologetically difficult. I could honestly go either way.
You get two games when you buy Shank. One's singleplayer, featuring the title character as he stabs, shoots, explodes, and chainsaws pretty much everyone he sees, as part of his campaign for revenge against his former boss. The other is a co-op game that's just about as long, and is set a couple of years before the other campaign, when Shank is still a mob enforcer.
Both games are side-scrolling 2D beat-'em-ups. You have a chunk of metal with a handle when you start the single-player game, and the further along you get, the more subweapons and guns you run across. You can chain your main weapon, subweapons, current gun, and a couple of different grapple moves together into a series of combo attacks that are surprisingly fluid, and it's all animated flawlessly.
When Shank is good, it's very good. It takes very little time to learn, and while you can mash your standard attack and get a certain amount of success, the fun largely comes from figuring out increasingly violent ways to take people out. I've found myself pouncing on guys and immediately jamming a running chainsaw into their chests, over and over again, to the point where I think it may be time to admit I have a problem. It's easy to move from enemy to enemy, blasting away with shotguns or an Uzi or cutting up entire groups with a pair of twin machetes, and the entire thing is accompanied by an absolutely brilliant guitar soundtrack.
This isn't to say that Shank is a spectacle fighter. It's a brawler like Final Fight or Double Dragon; you can take out enemies with a lot of style, but the game becomes significantly challenging about halfway through the second level. By the time you reach the final stages, it becomes surprisingly difficult.
That's fine, as far as it goes. The problem is that when I die in Shank, it's rarely preventable or understandable. A genuinely challenging game, such as Ninja Gaiden, is very good at telling you exactly how you screwed up and why, so with persistence, you overcome the challenge in an organic way.
In Shank, death frequently seems arbitrary. Boss patterns are there, but are inconsistent and usually obnoxious. Want to dodge rocket fire from the jeep at the end of stage two? That's cute. You probably can't. Want to jump over the two charging bikers in co-op mode? You have a very small window in which to do so, and if you miss, you've screwed yourself out of your only chance to do any real damage to them at all. Shank's boss fights stop all the fluidity and mayhem that you get from fighting the normal enemies, and replace them with a frustrating exercise in broken pattern recognition.
Most of the game is actually pretty fun, although the loading times are damned long for a downloadable title. It's a colorful, violent cartoon with some of the best music of any game this year. It's simply that any time a boss shows up, I want to go play something else.