This is amazing in any White deck, and is in a massive 7% of White decks
Its basically a repeatable discard effect since it triggers when dealing damage to opponents, and it has shadow
To make a deck like this work, you need a way to deal damage to your own creatures when you want (Walking Ballista, Pyrohemia, Lightmine Field, Staff Of Nin, or even Prodigal Pyromancer cards), you need creatures that will trigger for being dealt damage, and you need a way to control the incoming damage so you arent losing creatures you dont want to (such as to a Skullcrack or similar effect, or an early Star Of Destruction)
Read More: Exclusive Red-Bordered MTG Secret Lair Has Surprising Reprint Value On the Trail Any green deck that can consistently fulfill the draw 2 clause that On the Trail asks of multiple times in a turn cycle will go absolutely nuts with this card
This might be a sign to run a couple more big spells
But the selection of symmetrical effects every turn is what makes this card great, not to mention, with EDHs politics, your opponents will never know who youll help next