I think we can appreciate that everyone has a different idea of what's fun. According to the DCI, and probably for many people, playing against fast combo decks such as Reanimator and ANT are not fun. For others, getting locked out by Countertop or Dragon Stompy ruins there day. Still others hate getting their face bashed in by Zoo.

(begins rant)

I'm surprised I haven't heard much mention of Lands yet. I haven't played against it much, and although I've been 50-50, so far I've hated the experience. When I play ANT, it's just about the closest thing to goldfishing. When I play Zoo, I hope I topdeck one of my Price of Progresses. If so, the game ends quickly and mercifully.

Otherwise, I need to win a drawn-out 50 minute game (which I did once by decking the opponent naturally), or scoop quickly and hope for a match draw. Even when I'm not playing against Lands, inevitably, the matchup that ends up going overtime involves one of the Lands decks, with permanents on both sides of the board spilling over their allotted space, ending up in a 1-1 or even 0-0 after an hour of wasted time.

For the love of God, Lands players, please include a Mindslaver recursion condition with a Tolaria West search package so that the game can end mercifully

Edit: I think there's something fundamentally wrong with the deck when a successful play strategy includes taking as long as possible to win game 1 so that game 2 ends in a draw after extra turns.