Senntisten crystals are items found in The Empty Throne Room. They can be collected from the bin near the entrance of the throne room. They can be transmuted into yellow, green, blue, or red crystals, requiring level 65 Divination and granting 1.9 experience per crystal - or 19.8 experience for the colour that has a crate Empowered. The coloured crystals are then deposited in the relevant crate, giving an additional 19.8 experience (unaffected by the Empowered crate).
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