Granted, these types of abilities open up infinite loop possibilities, so Im never going to discount this Abzan treefolk shaman completely
You can also attend local events or play online
Most recent sets release 2 to 5 commander decks alongside the main set
As the owner, you shuffle it into your library and reveal the top card, potentially cheating a massive threat onto the battlefield for free
However, you can consider playing fewer than four copies of a card if: It gets worse in multiples (such as legendary creatures) It's only useful against certain matchups It's a win condition, and your control deck will have time to dig through the deck and find it You're stuck choosing between two cards which have equally strong, similar, but slightly different effects (you could play two of each) It's a slightly worse version of a card you have four copies of already, and you're including it because you want even more of that effect
It has all the efficiency of Counterspell with enough mana acceleration to play Eldrazi well before you should