If codes are ordered with physical items then the physical code
If you find a way to damage your opponent, either through combat damage or with a damage spell (such as [c]Lightning Bolt[/c]), you can play this spell for only one red mana, which is quite the bargain
I'm not calling a return of the iconic villain, but just reminding everyone that a metagame with no 25,000 power leaders could open the door for a return of yellow agressive strategies
Most decks, in order to fill in the 40-card limit, will also resort to splashable cards (that is, cards that can easily be added to most Decks to help the main strategy, whether they're monsters that are easy to summon, or Spells and/or Traps to help the Deck's strategy or disrupt the opponent's)
Just dont try to block attacks, since they all share a zero-point defense stat