Welcome to the roughly-10day-intervall-featured rules! These 10 days (well, week hopefully):
Trials stuff: Both players choose an element. In each deck at least 50% of the cards need to come from those 2 elements (note that your opponent may use your chosen element for that purpose as well).
And an alternative bonus rule to make up for the late post:
Red and blue: You can use red or blue decks (you may also play a red deck after a blue one and vice versa). Red decks may contain any
and
cards except firebolt and discord. Blue decks can contain any
and
cards except Shard of Patience and Owl's Eye. 12 upgrades, other cards allowed (but not from other elements, just the colorless ones), mark can be chosen freely.
The latter was a rejected tourney idea; if you try it out please remind me why it was rejected (it doesn't seem so bad).