All right. Let's see just how much damage we can REALLY deal in a few turns.
Opening hand: Forest, Island, Island, Misty Rainforest, Birds of Paradise, Lotus Cobra, Walking Atlas.
Turn 1: Play Forest and Birds.
Turn 2: Draw Birds of Paradise. Play Lotus Cobra. Play Misty Rainforest and fetch an Island, adding GR to your mana pool. Tap the Island and use the floating R in your mana pool to play Walking Atlas, then use the G to play the other Birds.
Turn 3: Draw
Brilliant Ultimatum
. Play Island, adding B to your mana pool. Tap Walking Atlas to put an Island into play, adding B to your mana pool. Tap both Birds for WW. With UUU from three Islands, BB from Lotus Cobra and WW from the Birds, cast
Brilliant Ultimatum
. The goldfish puts all five cards in one pile, so cast all of them. The cards, in order of resolution:
Dreamstone Hedron,
Cloven Casting
,
Cloven Casting
,
Cloven Casting
,
Brilliant Ultimatum
. The Ultimatum triggers each Cloven Casting. Tap the Hedron for 3 colorless mana and pay to copy
Brilliant Ultimatum
thrice.
Copy 1: Dreamstone Hedron, Dreamstone Hedron, Dreamstone Hedron,
Cloven Casting
,
Brilliant Ultimatum
. Tap two of the Hedrons for 6 and copy the resultant Ultimatum four times, one for each copy of Cloven Casting. You now have seven
Brilliant Ultimatum
s remaining on the stack and two mana in your mana pool.
Copy 2:
Pyromancer Ascension
,
Pyromancer Ascension
,
Pyromancer Ascension
,
Pyromancer Ascension
,
Brilliant Ultimatum
. Tap the Hedron and copy the Ultimatum four times. You now have eleven Brilliant Ultimatums remaining on the stack (that's 55 free cards), 32 cards in your library, and one counter on each Ascension.
First, cast your four Quest for Pure Flame. Quadruple Lava Axe powers up both the Ascensions and the Quests (the third and fourth Axes are copied four times each). Sacrifice the Quests as soon as they're powered up to multiply all damage dealt this turn by 16. That's 20 damage from regular Axes and some more from copies. Good start.
Now for creatures. Twenty Skittering Invasion nets us an even 100 Eldrazi, plus
Madrush Cyclops
for haste. Cast one Emrakul, the Aeons Torn for our second extra turn. Then, twenty-five copies of Nomads' Assembly, five of which are Reverberate and its copies.
You currently control 105 creatures -- three Birds, one Cyclops, and 100 Spawn. Now multiply that by two. Twenty-five times. 105 * 225 == 3,523,215,360 creatures. 3,523,215,255 of which are Soldiers. As a result, when you cast your four Coat of Arms, each Soldier gets a power boost of +14,092,861,016.
Then the Overwhelming Stampedes go off. Twenty of them. Which means each Soldier's power is doubled twenty times. Each Soldier currently has a power of 14,777,435,833,761,792.
Then four World at War for twenty extra combat phases.
For your 32nd free card out of 55, cast your second Emrakul. They both die to the legend rule, and your graveyard shuffles back into your library. Which means you can do most of this all over again.
Start with the Quests and the Lava Axes. Now, in addition to the extra Axe damage, damage dealt this turn is multiplied by a total factor of 256. Keep that in mind. That's 40 cards out of 55.
Then cast two more Skittering Invasion for 50 more creatures. Then four more Nomads' Assembly and a Reverberate for 25 copies. Then the four (twenty) Stampedes again, then the four (twenty) Worlds at War. You're finally out of free cards.
Total number of creatures: 118,219,491,896,197,120. All but 155 of these are Soldiers.
Total number of combat phases: 41.
Total power of each Soldier: More than 511,343,752,295,009,115,701,248. I stopped counting the Birds and Eldrazi Spawn a while back.
Total damage dealt: Uh... multiply the above by the total number of creatures, then by 256, then by 40...
The final result is somewhere around 6.1901617746545518218590419445733 * 10 to the 44th damage.
EDIT: People have complained that the challenge says I have to kill the goldfish in three "natural" turns, rendering my Time Warp-fueled deck invalid. TAMA has said otherwise, but instead of arguing the point, I decided to just go off a turn earlier. The deck now uses Walking Atlas and Lotus Cobra to do its thing on turn three instead of turn four. As an added bonus, I use fewer cards to reach
Brilliant Ultimatum
mana. Happy now?