Battle Arena is the online part of DQ. there are a few posts on which Crystals and Myth Stones can be used to modify Eternal Items and Pets. one of the hardest Crystals modifications to figure out is Jasper, since that changes an items Class to another Class, and that can be confusing to someone who doesn’t think to check other classes to see if that item was switched that way. if you see a modified Eternal Item or Pet that wasn’t modified from the list of Crystals or Myth Stones that can be used, then you have found a cheat/hack Item or Pet. I don’t know much about how the Dev’s seeing behind the code to find a cheat or legit player works, but I am sure it has something to do with seeing if they used the proper Crystals or an improper cheat.
here is a list I made of legit modifications for Eternal Items in the Arena:
I hope this can help players understand what items other players have in the Arena.