Regen is one of the top emulators of Sega Mega Drive games. The primary role of the emulator is to bring back the classic experience of traditional games, rather than upgrade it. Unlike other emulators, this one has been written with accuracy in mind – apart from the nostalgic experience, you also get all the little issues associated with those games. Compatibility is flawless and most games can be played with no issues whatsoever. It is worth noting that Regen only works on Linux and Windows operating systems.
The emulator comes with a series of features, including a stereo sound output, emulation for I/O ports, support for game pads, multiplayer support and save and load states. It offers full backup RAM support, as well as support for the Kega Fusion plugin. Make sure you get your own ROM images though, as the emulator does not include any. Other than that, you can use it for free.