This set transforms your regular PicassoTiles set into one that can build castles as tall as your kids! In terms of open-ended building toys, my kids agree that bigger is better. While I thought they were going to use the Large Connected Magnetic Tiles to build wider (horizontally), they decided to go vertical with the connected tiles along with our regular PicassoTiles set. The Large Connected Magnetic Tiles made it so much stronger and they were able to build a much taller castle than they could have with just the smaller tiles. This is an extension you definitely need to add to your collection!