Opposition Agent is a hard stop to all tutor effects, always
That already gives Celes, Rune Knight a strong ability, but much of its power comes from the second ability that puts +1/+1 counters on creatures that come from the graveyard
So, lets dive in
Whenever it deals damage, you can throw away your hand and draw equal to the number of artifacts you control, which, as any self-respecting cheerios player would know, simply means "discard nothing, draw your whole deck"
There's no indication of any major new mechanics in Azurite Sea , but there should still be plenty of appeal in the new set for dedicated Disney Lorcana fans
This way, a Temple Garden with a Blood Moon out will not have the Forest and Plains types, but will have the Mountain type, which will leave it with one mana ability to tap for red mana