Dom Dom, the Stormchaser

As long as Dom Dom, the Stormchaser is tapped instant and sorcery spells you cast have Goblin Overload. Its Goblin Overload cost is equal to its
mana cost plus {2}. (You may cast this spell for its goblin overload cost. If you do, change its text by replacing all instances of "target" with
"each Goblin".)
{t} Sacrifice a Goblin: Create X 1/1 red Goblin creature tokens, where X is the number
of spells you've cast this turn.