I just got Mystic Formula in today, and I popped it in and tried it out and it seemed okay. Then, a little while later, my friend and I decided to play it as 2-player simultaneous. We enjoyed it so much, that we went ahead and played it all the way through and beat the game. We really enjoyed it. It's basically an overhead run-'n-gun similar to Pocky & Rocky for the SNES (or Kiki KaiKai for the PC Engine), The Chaos Engine/Soldiers of Fortune, or the overhead levels of some of the Contra games. If you enjoy this style of game, then I definitely recommend that you get this game, even if it's a titch pricey.
You have a choice of 4 different characters to play as, and each has different stats (speed, strength, etc...) and a different weapon with different powerup trees. For example one character, the green-haired girl has a homing flamethrower which is slow at first, but as it powers up, it can shoot faster and faster, while the blue-haired guy's laser upgrades from a single beam to multiple beams. You can even change characters when you continue if you like. You also have a straffing button with which to lock your firing in one direction only (think shooting to the left while walking to the right), and you have bombs magical scrolls which damage or destroy everything on the screen.
