Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.) Whenever Academy Raider deals combat damage to a player, you may discard a card. If you do, draw a card.
Official Rulings for Academy Raider
7/1/2013 : The triggered ability triggers just once each time Academy Raider deals combat damage to a player, regardless of how much damage it deals.