Metal Slug is one of the best classic action game games. Here you can play Metal Slug online for free. You take the role of a solder who must shoot all the enemies in front of him. If you want to reach the end of each level you must shoot а colossal amount of bullets. When you get the end of each level there is a boos who is stronger from the regular enemies and needs more gun power to be killed. During the game you will fin new weapons upgrades and “Metal Slug” tanks which you can use as weapons or defense. There are a total of six levels. They include forests, garrisoned cities, snowy mountain valleys, canyons, and military bases.