To get core hyren: 
You have to beet the 5th shadow gyser. before you do, 
make shure you save atleast 2 star keys. go to the one 
cave that apears after you beet the first gyser. go down 
the stairs at the left side of the cave. once you teleport 
you will be in a strange room that looks like the shadow 
hold. at the to center there is a gate. open it with the star 
key. inside is the ringsmith fallowed by many other rooms. in 
the final room you can fight the CORE HYREN and get its aminite. 
The problem is that you need like, 5 core hyren and 3 thunder hyren. 
I think you get thunder hyren by doing the orathan f. cheat 10 times 
and then look in the palace at the left of the 2 mountians. 
The other star key is for another secret, but i kant tell you that one.
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