The ever-evolving list from Wizards of the Coast bans and restricts previously released cards, so that cards that end up becoming too powerful and give players an unfair advantage can't be used in tournaments
If you already have countermagic in hand, this is a great way to induce a split that is more favorable for you than normal
Its cost is also reduced by for each instant or sorcery youve cast so far this turn, meaning you often see it cast for free
They are designed to be fun and competitive right out of the box, and they capture the spirit of the format in a way that feels welcoming even for new players
With a Pot of Greed and other spell cards that allow for multiple drawings, its attack can grow wildly out of control
It sort of gives you a little short burst, instead of a half an hour long game, which can be a positive in some scenarios