While Betrayal has some utility in Blood decks like Anje, Maid of Dishonor, Dungeon Delver is pretty much hard-locked to Sefris of the Hidden Ways
If you're building or maintaining a couple decks each season, each new release should provide a handful of upgrades for decks you already have or inspire you with an all-new deck to work toward, but the number of viable decks you have shouldn't change significantly
The face-down morphed card remains hidden until it turns face-up, moves to a zone like the graveyard or exile
I'll add on a follow-up post with more technical details once I know them, but for now I hope this helps you assess the battles you see during spoiler season
cards on your field is equal to or less than the number on your opponent's field, this Character gains +1000 power
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