I've seen a lot of bugs in many games, but I think Hearthstone is a unique one when it comes to one thing:
how come every bug that this game got has negative effect? not a single bug that has "positive effect"
(edit: I guess that Living Roots becoming epic can be considered as a positive one, but the effect was still minor)
-oops, you got no daily quests
-oops, no xp for you
-oops, no rewads for you
-oops, no free legendary for you
(the ones I remember from past):
-oops, the arena rewards didnt register
-oops, the pity timer didnt worked for you
-oops, you missed the heroic brawl, we replaced it now so no rewards for you
-oops, some of the cards are missing
-oops, some of your cardbacks are missing
why there were no bugs that benefit the player?