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A very special ring that is given to the Sky Knights. This ring is very unique as it allows the wearer to summon/unsummon/modify the Eisenmeteor. Each ring has the kanji for sky (空) which is used to summon an eisenmeteor as well as to summon other sky ring wearers. The ring also has 3 smaller seals inside of it that allow the transformation of the user's eisenmeteor into 1 of 3 possible forms that the ring was imbued with. So each ring is uniquely tailored to the indiviudal who wears it and the user is able to quickly swap between forms to adapt in battle. There are a total of 10 eisenmeteor swords that are locked away in an undisclosed location.