Play Metal Slug: 1st Mission online in your browser and enjoy with Emulator Games Online! Metal Slug: 1st Mission is NGP game USA region version that you can play free on our site. This game has arcade, shooting, action genres for Neo Geo Pocket console and is one of a series of action games. If you love action games you can also find other games on our site with Retro Games. Below you will find control for the emulator to play Metal Slug: 1st Mission.