12 Damage Counters is nothing to sneeze at and it could be seen as a 1-turn immunity for the Pokemon using it
Any trading card game demands that all cards have identical backs, so unsleeved cards can remain anonymous in a player's hand until they are used
Oona also works particularly well with cards that check when creatures come into play, like Kindred Discovery and Dire Undercurrents 3 Tegwyll, Duke Of Splendor A true Faerie lord, Tegwyll, Duke of Splendor works to give your other Faeries a boost in power while ensuring that you can still gain advantage even after death
If you need more colors, then fill in with cheap always solid staples like Command Tower, Path of Ancestry, and Myriad Landscape
And now I have the added benefit of optimized proxy manabases for every color combination, so that will make it easy for me to swap into a new deck without having to re-sleeve all my fetches, duals, shocks, Arcane Signets, etc