Select the difficulty and change the default keys to whatever you like. The pages are in Japanese, but I'm sure you can figure it out!
The Metal Slug game series is a platform shoot-em-up with amazing visuals and fantastic sense of humour. Not taking itself too seriously, but with a consistent and escalating frenetic energy, it pretty much is the greatest 2d coin up ever made.
As hard as the games may be, it never stopped gamers from slapping more and more coins into the machine, such is its playability. Less a game that one can actually win via strategy or know-how, it is pure button-mashing and perseverance, the ultimate two-player experience.
Starting in the mid-90's in arcade form, the games have since been ported to several game consoles, and have now run over to convergeance devices and smart tablets.
So take a break from all of this movie watching, and go nuts with the game that took the 2d platform to the edge!