MagicEngine is a PC-Engine console emulator.
The PC-Engine - also known as the TurboGrafx-16 in the USA, was a nice little machine made by NEC. The first model came out in 1987 followed one year later by a CD extension that made the PC-Engine the first console to have CD games.
This was quite an impressive machine, with good graphic capacities (16-bit video processor, 512 colors, 64 sprites) and a fast and powerful 8-bit CPU. It also had a very good game collection, with unique and high quality games. And even today some PC-Engine games are still without an equivalent on modern consoles. Of course if you only enjoy 3-D games, well, the PC-Engine may disappoint you a bit, but if you love good old 2-D games, especially shoot'em up, give it a try, it really has some excellent games!
But we are sure that you already know all that.
Go find those PC-Engine CD-ROMs that you stored in a cupboard a few years ago, remove the dust on them, and go downloading MagicEngine!