The Mystery Plate (133 / 144) card can be found in the Skyridge set.
Recently sold 1 times and based on those sales is worth around £7.70.
Currently, there is 1 open listing for this card on ebay.
This card sells in the range of £7.70 to £7.70, making it very stable.
This Uncommon card was illustrated by Hiromichi Sugiyama.