User blog comment:Arezaei/Battle Arena Records/@comment-108.48.163.199-20130529150124/@comment-9817652-20130529165618

We don't have any info. on Mercury itself, but Diamond based dragons seem to have a weakness for "Passion" element dragons, like Passion herself, left & right heart dragons. However, people have reported that they have lost with them, but it depends on their level. Note that the comment above you lost against a lvl 13 Anubis (diamond base) with Passion (lvl unknown). Let me know how it goes, we need some info. on how to beat Mercury.

-Armin