Thought of a better idea- what if when you touch a key, the blocks don't change, but instead only you and whoever else who touched the key can go through?
Click [+] if you want: Chat, Usernames on Hover, Admin Ban, Edit AND Admin code, Linked locks (1 lock to 1 door, not 1 key to a whole span of random doors), Room save, Gravity On/Off, Invisiblocks, and/or a gun.
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