If the total Levels of monsters you control are 10 or higher: Add to your hand or Special Summon 1 Level 10 monster from your hand or Deck. If the total Levels of monsters your opponent controls are 10 or higher: You can banish this card and 1 Level 10 monster from your GY, then target 1 card your opponent controls; banish it. You can only use 1 "Northern Crossfire" effect per turn, and only once that turn.