GraviTrax Go: Flexible is designed as a grab and build way to learn the basics of GraviTrax without needing a huge layout. Inside you’ll find track pieces, height tiles, special flexible elements and guided tasks that show how changing angles and paths affects marble speed and flow. Once you’re comfortable, you can ignore the sample builds and mix these pieces into any GraviTrax CORE, PRO or POWER setup for more twisty, creative runs.