Crystals

Crystals in Sword Art Online are considered to be one of the most convenient types of items and the closest thing to magic in the world. They have different uses, namely having immediate effect for recovery unlike potions and perform a variety of function outside of healing, extending to teleportation, corridors to locations, and displaying images or replaying voice messages.

Though extremely useful, they are expensive hence making people hesitant to use them, unless they are in very special (dangerous) situation. Most of crystals can be found through some NPC shops, except for the Corridor Crystal. Corridor Crystal only can be obtained from player trading and monster drops.

Their usage can also be prevented by a trap called an anti-crystal field, which became normal for boss fights on the 74th Floor and above.

Known Kinds

 * Antidote Crystal (Green) - cure any status effects.
 * Health Crystal (Red) - completely heal the target.
 * Mirage Sphere - Able to record mapping data.
 * Teleport Crystal (Blue) - transport the user to a chosen city's Teleport Gate plaza.
 * Corridor Crystal - a larger form of teleport crystal that opens a teleport gate to any location that the player has marked.
 * Record Crystal - record what someone has said.

Colors

 * Amaranth/Red - Full Health Recovery
 * Blue - Teleportation
 * Blue with Red Dots - Corridor
 * Green - Status Recovery
 * Light Sea Green - Record Crystal (when recording or playback)
 * Teal - Record Crystal (when inactive)
 * Gold - Mirage Sphere (When active, its top bursts open to reveal a map of various floors that have been discovered, and areas therein)

Gallery
Cristales Crystals Кристаллы