Here's how it works.
We spend the first 7 turns dicking around trading minions and accomplishing nothing of real substance.
Then I play my 8-mana card that wipes your board and floods my own board.
In response, you play your 8-mana card that wipes my board and floods your board.
We do this until one of us runs out of busted 8-cost legendary cards and dies, then we requeue and do it all over again.