I'm pretty sure the house has always had a 1% house edge, and I'm almost certain there was never a 0% house edge.
We've always had 1% edge, but the effective house edge is a bit smaller since your rakeback rate increases the longer you play. During the competitions it was not uncommon that the game itself proved to be in favor of winning players.
Right now the prize pool is
over 45 ETH, and there is over one day left.
Cheers,
Ethan