One is for everybody to wear and use the spell and one is for myth students only. The amulet that lets everybody use it is a bit rare in the bazaar. Or is it just this is my first time seeing it. Lucas drakebloom Level 46 Ice wizard Sword saint
Cronius' Continum Circlet is level 45 and is only wearable by Myth students. It's dropped by Cronius (Crystal Grove). There are generally 100 of these in the Bazaar, and the cost is about 3300 gold.
Plagued Collar of the Beast is level 35 and can be worn by any school. It's dropped by the Plague Oni and can be used by any school. Since this amulet can be worn by any school and has a lower level restriction, it's harder to find at the Bazaar. It can cost up to 5100 gold.
