Spatial Merging is a common Phenomenon card from March of the Machine Commander (MOC), collector number 158. Current market price: $0.36, TCGplayer market prices via Scryfall.
When you encounter Spatial Merging, reveal cards from the top of your planar deck until you reveal two plane cards. Simultaneously planeswalk to both of them. Put all other cards revealed this way on the bottom of your planar deck in any order.