Most people who own a playset of Lilianas arent going to sell their copies theyre going to shrug, assume that the card will be useful again in the future, and stick them in a box until that day comes
Magic: The Gathering is entering the nuclear apocalypse in Universes Beyond: Fallout
Flanking means "Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn." If a creature gains flanking during combat, that has no effect on any creature already blocking it
So Gold Tier I is much better than Gold Tier IV, even though both players are technically Gold
Meren made an impact on the format immediately, with a lot of valid hype
At four mana, and considering you need a way to make sure it goes to the graveyard, this symmetrical effect may not seem too strong