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[edit] User Interface

While playing there are 2 numbers that appear on the screen informing you on your progress.

• Score: Located in the top-left corner, it tracks how many points you gain from killing enemies and the like. It goes back to 0 once you get a game over.
• Time: Located in the bottom-left corner, it tracks how much time you have left to complete the stage. This isn't that important really; you should have more than enough time to do everything.