Game cartridge only. 112 Hot games in one cartridge for Sega Genesis! Please look at pictures for complete game listings. FUNCTIONALITY COMPATIBILITY Works perfectly in an original Model 1 or 2 Sega Genesis or Mega Drive system. Mini Gen, Retron 3, Retro Trio, Genesis 3 and RetroAD systems also work perfectly. Nomad handheld systems will have many incompatibilities and are not recommended. Retron 5 WILL NOT WORK - it is an Android emulator, not hardware, and cannot load multiple files. ATGames systems WILL NOT WORK. This means the Classic, Flashback, etc. They will only ever load one wrestling game and no menu. If you have one of the newer tiny systems with 80+ built in games, that is an ATGames system and WILL NOT WORK! All games are full versions. In-game codes and passwords work like you remember. PAL and NTSC compatible.