This deck contains all of the cards you'd need to potentially do over 4 million damage for just nine mana. The odds of doing this perfectly are incredibly low, but I just wanted to use this to demonstrate that it is theoretically possible to do 4 million damage for 9 mana. You can do the same with Incierate, but for 10 mana instead of 9.
First, get out every Pyromancer Ascension and Quest for the Pure Flame. Play three lightning bolts, so that PA has both counters, and play Geistflame for the final QftPF counter.
Then, get out all of your enchantments, creatures, etc. that do double damage.
Then, get 9 mana total, play your last Bolt, then copy it four times with Reverberate, and laugh as you have done enough damage to win 245,760 games of Magic with 9 mana.
Pyromancer Ascension, when it has both counters, copies every spell, and if you have four, that's four copies each. Play one bolt, it's copied four times. Play four reverberates, that's 20 reverberates, all targetting one lightning bolt, that's 25 lightning bolts. With Fire Servant, Furnace of Rath, Quest for the Pure Flame, and Curse of Bloodletting all doing double damage four times, that's 2x damage 16 times on 25 lightning bolts. Initial 3, then 6, then 12, etc. all adds up to 4,915,200 in total.
Oh, and if they manage to survive that, you've always got a Geistflame you can flashback.
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