If you set the proper doormode in the settings all doors (all door tiles) will open and close randomly.
You can set the doormode to random by typing: (You need to have Sysop access or owner access to the arena for this)
You can also set it to -1, it will be less random then (weighted random: some doors open more often than others).
The speed the doors open / close randomly can be set with DoorDelay.
You set it the same way as the doormode, but replace 'doormode' with 'doordelay' and specify the time (ms?) instead of -2.
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