The core of a Jedi’s lightsaber is the focusing crystal, which the Jedi must attune and imbue with the power of the Force. Natural crystals suitable for lightsabers are rare, but not impossible to find throughout the Galaxy. The Jedi Order has harvested lightsaber crystals from the planet Ilum for generations, and guards the planet closely for just this purpose. In order to attune a crystal, the Jedi must make a Difficult Force roll; for each day the Jedi spends meditating and preparing for attunement, the difficulty may be lowered by 5. The attunement takes at least one full day, during which time no other actions may be taken. If this roll fails, the Jedi must begin again, though failure does not cause damage to the crystal.