John of Patmos is clearly Christian mysticism
Would you class the Transfiguration as a mystical experience from the point of view of Peter, James and John? I think you’d have to.
John was not seeking personal revelation nor did He say or infer a oneness with God ...God gave him a vision that was to be recorded as the final revelation to the church until Christ comes again .. although Catholic teaching is that it is actually a historical allegory...A-mil theology