You can draw on the magical energies within a Z’lethan crystal to restore your own strength. By holding a crystal in your hand and using an action, you gain the benefits of a short rest. After you’ve used the crystal in this way, roll a Wisdom saving throw against DC 12 or also fall unconscious for one minute (even if you are normally immune to sleep).

Once used, the crystal loses its glow and becomes a dull blue crystal worth 10 gp.