The Cragsters came across boulders containing crystals inside.
- They are found in boulders in the Mine. They are more common in larger boulders than smaller ones.
- They have three variants: green, gold, and red. The green variant is more common.
- The larger ones are so hard, even one Cragster can have a hard time smashing them. But when three Cragsters Max, it is easy for them to smash through it.
- Shuff, Chilbo, and Slumbo have a crystal on their heads. In Chilbo and Slumbo's cases, it is an ice crystal. Chilbo's crystal is also his brain.
- Chillbo's crystal is brick-built, while Shuff's and Slumbo's use single crystal pieces.
- King Nixel wears one on his head, resembling a crown.
- One of Dribbal's pieces used for snot in his LEGO set is a transparent lime green crystal, the same piece used for Shuff and Slumbo.
- Giant crystals are an obstacle in Mixels Rush. They are partway embedded in rocks here.
Mine (Krader's House / Shuff's House) / Rockball / Digging / Crystals / Mt. Brushmore / Cart Crashers / Snail Mail / Typewriter / Minecart