How to calculate your score is in the notes and credits. Each time you move up a level by touching the time vortex, new enemies will appear and your location will reset. Use the arrow keys to move the TARDIS to the time vortex, a.k.a. the swirly pinkish purpley mess. Touching enemies will make you lose your regenerations, which you have five of. Your enemies are the Daleks (spotty hamburger monsters), the Weeping Angels (grey blobs on the sides of level two), and the Cyberman (swirling robot guy on level 3).
This is only three levels so far and a kind of short game, but if you guys like it, I might add more... be sure to let me know by liking, commenting, and favoriting (wow way to be subtle there)~! Help the Doctor travel through all of time and space by avoiding enemies and reaching the time vortex. Keep in mind, of course, that the TARDIS may be hard to control at times.... after all, it's supposed to have six pilots. Get your score by multiplying your number of remaining generations by 100 and subtracting the amount of time you took to end the game. (Isn't the little Doctor in the corner just so adorable with his sonic screwdriver aww)