Any time an opponent might want to cast an instant or sorcery spell, theyll have Niv-Mizzets ability to consider
Even just catching a Goyf and Spirit team is huge, especially if you used your 2nd and 3rd turns to play noncreature cards
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
4) Hatred Black weenie decks owe a huge debt of gratitude to this instant, which gave shadow creatures on average an extra eighteen power on turn three (thanks again to a certain other instant/interrupt/mana source that I'll get to in a minute, promise!)
Countering a five or six mana Commander with this feels criminal, and if you can follow it up by dumping your hand into play, well youre in great shape