You can only trade in a rare card if you would still have two copies of the card after the trade
I realize thats rarely what you use this card for in your rogues and/or spirits typal decks, but you could
Once you've survived your opponent's early onslaught, there will come a turn when you can fire up your creature lands and make a big attack back, suddenly putting your opponent on their heels
The Gold and Platinum memberships make it more affordable for people to submit bulk orders
In most cases, your opponents will probably just let the damage through, but once it gets buffed and is swinging for 4, 5, 6, or more damage, they will likely be forced to block
As Gandalf said: Show us the meaning of haste. #31