Black crystals are encountered during the fight with Seiryu the Azure Serpent. They are found on the shackles that imprison the serpent. All three have to be destroyed in order to free Seiryu and end the fight. They can only be destroyed once the player has jumped onto the shackles after dealing 300,000 (150,000 in story mode) damage to Seiryu. Several shadow enigmas will approach Seiryu soon after the crystals become attackable and will heal all crystals for roughly 50,000 life points each if any reach Seiryu.
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