The ability triggers (see Rule 404) on the declaration of attackers. [D'Angelo 1998/06/03]
You either take damage or pay the 2 mana during resolution. [D'Angelo 2000/02/25]
Extended tournaments (see Rule 803) have banned this card since 1999/10/01.
Note - The Arabian Nights version of this card has two versions, one with a small dark circle behind the "2" in the payment cost (rarity C3) and one with a normal mana circle behind the cost (rarity C2).