The latest week-long Tavern Brawl event mode in Hearthstone is an interesting one, letting players use decks that have won previous Hearthstone World Championships - in their original, unnerfed forms. Some of the cards in these decks have been rebalanced, see, but here they're fighting at full strength. Say hallo again to Knife Juggler, Azure Drake, Undertaker, Leper Gnome, and their overpowered pals. The decks span the 2014, 2015, and 2016 Championships so it's a neat chance to pit different eras of Hearthstone against each other too.
The 'Hall of Champions' Brawl supplies players with twelve World Championship decks from Pavel, Firebat and Ostkaka - one deck chosen at random when you play. The decks are obviously powerful--especially given that cards are reverted to their previous forms--but some deck types and combos might be unfamiliar, so you might need to study up. Or laugh and reap the victories as opponents struggle to play a deck well.
I remember one chum bought some of Magic: The Gathering's pre-built World Championship Decks way back in the day and we, being scrubs at the time, couldn't figure out quite how they worked or why they were considered so powerful. Bless. Dear little idiots.
Some people are reporting finding the odd card or two hasn't properly reverted to its era-appropriate power levels, though these seem to be the result of oversights or glitches rather than intentional decisions by Blizzard.
The Tavern Brawl will end next Wednesday, but hopefully it's one Blizzard will bring back in the future - with more decks.
All of this is to celebrate this year's World Championships, which are going on this week. They're livestreamed and whatnot, if you're curious, and player decklists are over here. And hey, whether you care about digital sports or not, you can score free card packs by picking a favourite.