It was Storm of Stone that became his choice of the extra card to be discarded. The reason for it was that he felt that the required earth mana source for paying the cost of the card would not be possible anymore for him to achieve it at this point of battle. The damage that was caused by Burn the World was too much that it made his asset rebuild not go as smoothly as Ahli had expected. He realized that he had made a mistake in choosing Storm of Stone to be returned to his hand earlier.
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STORM OF STONES
┌ X + Earth + Earth + Earth ┐
╠ Magic Spell ╣
Each opposing card mage loses 3 life
points unless they discard a card from
their hand or sacrifice an active spell
they controlled. Repeat the process X
times
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