347 votesBen supported this idea ·Ben commented
Seconding that TCG comment. This is a very common way to format large open tournaments for card games, e.g. Magic the Gathering, Game of Thrones LCG, Netrunner LCG, etc.
Just as the OP said: Swiss first stage, cut the top performers to a single elim playoffs.
I'd like to try this with Hearthstone.