Step 1: Movement

Anybody caught using the default platform movement is appropriately punished by death, so, it is required we create our own custom platform movement. As follows:
The events above move the player left and right while holding the arrow keys. The negated opposite direction is required to hold the player in the current direction if the user presses both keys at once.
Now, we must resume the Stopped animation if the player stops moving, or presses both keys at once. Note that pressing both arrow keys with the default platform movement will make the player move left. This will never happen in any real game!
This will stop keep the player within 32 pixels of the left and right frame edge. Lastly, we must center scrolling on our player, and while we're at it, why not hide the mouse cursor.
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