2004-10-04 : Multiple Gates are cumulative. Two will reduce the cost by up to {4}, and so on.

2004-10-04 : Only reduces the generic mana portion of a spell’s cost. If the cost does not include generic mana or includes less than {2}, you get a reduced or null effect from this card.

2004-10-04 : Only works for its controller, not all players.

2008-04-01 : Works on all spells with the type Creature, even if the spell has another type like Artifact or Enchantment.