The most important development in the last 20 years has been the introduction of the EX cards, one card that is a particularity strong, but carried the risk of losing two prize cards if defeated
Being colorless and mana efficient, this little utility has a lot of potential to prevent a blowout
Granted, those decks are almost all focused on milling out the opponent but the original Hedron Crab is also able to target yourself, which makes it one of the most explosive and mana-efficient self-mill engines ever printed
Its got a pretty neat ability, too, allowing you to transfer all of its energy to another Pokmon upon being knocked out, instantly letting you set up another Pokmon on the bench
Special Summon this card from your hand, and if you do, return that targeted card to the hand
Going first is vital in the mirror, as the first player to establish Colossus with protection has a commanding position