Any% (Beat the Game) - Basics

Essentially you are trying to complete a new game file as fast as possible. This includes the player beating all 8 missions, and then after the credits, they will be presented with a "CONGRATULATIONS! You Beat Martian Panic screen, in which the run ends.

Though this is simply an on-rails shooter, there are many ways to improve times for this game. Some basics are...
-Good efficient shooting thus moving through levels faster
-Implementing useful power ups and items
-Dying as little as possible because having to press "continue" loses time
-Fast Menuing and Skipping cutscenes when possible.
-Spamming Bosses to end the fights faster.

For Any%, the player should play on the Cadet (easiest) difficulty due to the fact that you get unlimited continues, this makes it much easier to kill enemies and not have to redo entire levels...

There is also the option of playing Dual Wield mode, where you hold two Wiimotes acting as two separate guns, this could be a very efficient/faster way to play, but it does require a lot of multitasking. Do what feels more comfortable to you in the beginning.

Make sure that before each run you delete the previous savefile and are playing on a New File so that you can get the "You Beat Martian Panic!" final screen to appear. This helps ensure that you have completed the game.  (You can do this by going to Wii Data Management, on the Wii Menu, and erasing the data of the game)

This game can be found very cheaply online and at various Videogame stores. I got my copy for $1.99 at a random Gamestop.