If you dont see this as the centerpiece, then the fact that its cost is very flexible should still make Oona a very desirable card for some control and mill decks
In our example below, we select 1963 Gordie Howe Parkhurst cards that have a grade of 7
(The link will open in a new tab) Duelist's Advance Booster Pack Do do do do Duel, with Duelists Advance
Search your library for a creature card with mana value X or less, where X is 2 plus the sacrificed creatures mana value
Sidisi, Regent of the Mire Sidisi, Regent of the Mire is a zombie Birthing Pod, so naturally it works with the graveyard rather than the library
"06 - Amy" + 1 "Super Shadow" When this card is Synchro summoned, Banish all cards from your opponent's graveyard, and this card gains 300 ATK x the number of cards banished by this effect