Water queens may be way overpowered.

[Tuidjy]

Argitoth. That particular water queen can be easily killed by a fire mage
casting Heat from Hell, teamed with a fire immune bane lord (for example) who
does enough damage to get through the regeneration. By the way, she is not
particularly well equiped - one can do MUCH better.

But in general, many players rank Elemental Royalty like this:

Air Queens
Earth Kings
Water Queens
Fire Kings

While in general I agree with the above, in many cases, some of the lower rated
royalties are better suited to a task. But as a rule, to kill a SC, you tailor
an attack for him. Then your enemy teleports his counter, and probably win.
There is NOTHING that is unbeatble, except for Mist of Deception cast by a
defender who retreats on the next turn.