This is the Mryagut High Legend Burgle Rogue Deck he was playing on stream in the top 5 legend ranks. Any deck that can win that high on the ladder is pretty good, and although there is a load of RNG in this deck it seems to find some consistency.
The random cards from your opponent’s class can throw anything at you, and that’s the main criticism of the deck. But when you’re lowering their cost by 2 even average cards become pretty good.
Any cards that allow you to ‘cheat’ mana in Hearthstone have proven to be pretty good. Just look at Mysterious Challenger, Druid ramp decks, renounce darkness decks (ok maybe not renounce darkness decks).
Give this list a go and see how you get on.