The Mystery Energy 166/171 Reverse Holo Starfoil card from The Best of XY set is a highly collectible item for Pokemon TCG enthusiasts. This Japanese language card, illustrated by 5ban Graphics, showcases the character Mystery Energy in a standard-sized card made from card stock. With its special energy attribute and unique reverse holo design, this card is a must-have for collectors looking to add a rare and valuable piece to their collection from the year 2017.