A Trestle Tracks Builder Set is a unique, slow-paced marble run toy by Fat Brain Toys, featuring flat tracks with subtly widening paths that propel marbles using an optical illusion, built with hollow stacking cubes (risers) to create suspended structures, encouraging spatial reasoning and engineering skills for ages 8+. The Builder Set includes essential pieces like tracks, risers, marbles, a catcher, and a base grid, offering guided builds and open-ended creative play.