Check the listing for details. Tower Stacks ( Castles Version) By Smart Games Solo Puzzle.. Color: Multi-Color, Condition: Used. Listed at 19.99 USD. Tower Stacks (Castles Version) by Smart Games is a solo puzzle game featuring a twist on the classic Tower Stacks concept. This version of the game focuses on medieval castles, adding a creative and engaging twist to the puzzle. Made of durable plastic, the game's cube/twist puzzle structure challenges players to strategically build and balance towers in a 9x9x9 space. With a colorful multi-color design and an age level of 8-11 years, this puzzle game is sure to provide hours of fun and cognitive stimulation for young puzzlers. Has 80 building challenges with included instructions ranging from easy to expert for ages 8 to adult. Item is complete with all components in excellent condition. Box has some minor storage wear.