Assassin. Loner. Otaku. Luchador. Virgin. These, among many other things, define Travis Touchdown, the lightsaber-wielding manchild protagonist of NMH2. It's a refinement on the first title, both in tone and gameplay, and integrates the Wii motion controls without abusing them (no remote flailing). It's a funny, irreverant, and bizarre game, and is utterly unique. Except for the first game, obviously.
A beat-em-up RPG from the makers of the woefully-underplayed Odin Sphere, Muramasa is the most beautiful goddamned game ever made. Set in mythological Japan, two tales of revenge and redemption stretch from the depths of Yomi to the heights of Mt. Fugi. The RPG elements are deep without bogging down the action (like Odin Sphere did at times) and it has a wealth of hidden challenges for completionists.
Joker takes over Arkham, starts releasing villains, Batman the only one who can stop him, you get the jist. Story isn't anything too special (voice acting is though), but the real star is Batman here and boy is it awesome. It's a hybrid between stealth, beat-em-up, and Metroidvania, and it pulls off each element so tightly you hardly even notice. Gadgets are numerous, but plausible (no anti-thing spray) and most have a use in combat, if you really want to get fancy. Only downside is your throat might get sore from growling "I AM BATMAN" every time you do anything.
Witch with guns on every limb and magic hair killing angels BDSM style. There, now you know whether you want to play Bayonetta or not.
2009 marked a surge of 2D fighting game interest, and the two giants here were SF4 and BB. 2010 brought the refined sequels you see above, both adding more content and balance tweaks. They're both great games with balanced rosters and tons of depth while being pretty newbie-friendly. If you can only get one, all else being equal, get BB: the netcode is far better, which makes online play more than an exercise in dropped inputs.
The scourge of gaming as of late has been open-world adventure games (I hate calling them sandbox games because you can't win at sandbox) but as overused and trendy as the feature is, some games get it right and properly need it. Of the three InFamous has the best combat and difficulty curve, ACII has the best freerunning and graphics, and Prototype has the best being-a-dick-catharsis factor. Word to the wise though, set the difficulty in ACII to hard. I played it on normal and guards literally were never threatening ever ever.
MOTHERFUCKING DWARF FORTRESS. Yes I know it came out in 2006, so maybe it shouldn't count. And yes it's ugly as sin and with a learning curve like a wall covered in deadly spiders. But recently the entire game got overhauled and turned 3D - not in graphics but in gameplay, which is enough of a difference for me to squeeze it in. It's a proper sandbox game with no way to win and oh-so many ways to lose, and a skull-crushing level of depth and complexity. Minecraft is for pussies, real men choose DF.