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probably the easiest method would be to duplicate the gate but make it require a different key
set the 2nd gate to spawn at start = no
put a trigger zone inside the "trap" area and make it spawn the 2nd gate and destroy the first gate -this can be done with a trigger zone but you will need to add Destroy(#) (# is the entity number of the first gate) where it also destroys itself (i.e. above Destroy(e))
