If your Fortitude Rating is less than your opponent's, take any 4 cards from your Ringside pile and shuffle them into your Arsenal.
If your Fortitude Rating is equal to your opponent's, remove any 1 card from your opponent's Ring area and place it in his Ringside pile.
If your Fortitude Rating is greater than your opponent's, look at your opponent's hand and choose 1 card he must discard.
Unique