Family Games XS Head Stress Wooden Brain Teaser Puzzle (Serpent Cube) This kit includes step by step solution instructions Difficulty Level: Hard All wood used in manufacturing was either from surplus wood from furniture factories or farmed trees from re-growth forests Family Games' remains committed to selling safe games and puzzles of the highest quality XS Headstress complex wooden puzzles taunt, tease and tantalize players to step up to the plate and challenge themsselve