1. Change the colors of the arrows by pressing the small triangle next to it. Change the direction of the arrows by pressing the arrows.
On each set of 4 arrows on the left, you have to look at each corner separately and find the pattern. For example, the top left on each set is RED UP, GREEN LEFT, BLUE DOWN, WHITE RIGHT. You have to find the next in the pattern, which in this case would be UP again and RED again.
Find the pattern in the direction and color for each arrow.
Pick up the key and use it on the door.
2. Proceed to the next 100 Doors Underground level!
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