When Rise of the Hobgoblins enters the battlefield, you may pay . If you do, put X 1/1 red and white Goblin Soldier creature tokens onto the battlefield. : Red creatures and white creatures you control gain first strike until end of turn.
A river even the merrow dare not cross.
Official Rulings for Rise of the Hobgoblins
8/1/2008 : When the enters-the-battlefield ability resolves, you choose the value of X, pay for it, and put the tokens onto the battlefield. You can activate mana abilities to pay for , but no one can cast spells or activate abilities in response to this choice.
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