Not sure how popular this strategy is; no one ever played it against me, and I didn't see it in the HSGuru wild meta list. A few days ago, I saw a youtube video where Clark Hellscream used [[Gemstone Hoarder]] to loop [[Play Dead]]. The idea was to trigger a deathrattle multiple times using [[Confront the Tol'vir]]. In his video, he used [[Bad Luck Albatross]] and [[Plated Beetle]], which seemed unoptimal.
I tried to make my own version that relies either on minions that damage the opponent directly or looping the [[Amphibian's Spirit]]. Surprisingly, this strategy is very consistent with the earliest OTK possible on t4. Arguably, the combination of Gemstone Hoarder and Play Dead is one of the strongest engines for deathrattle-based combos.
Since updating my deck for the last time, I played 10 games and won 7 times which proves nothing, but among all variations of this deck, I played 65 games with a WR of 53%. TBH, the low WR is my fault as I did a fair share of mistakes. In better hands, this strategy should perform much more successfully.
Here is my deck code.
AAEBAR8I1hGGwwLTzQLd9QLlsATQwAbi4wbRwAcLkgWAB9jCApzNAqmfBJXiBuyCB7vAB97EB4zGB+75BwAA
Among its strengths, it has a lot of draw and a consistent combo; it can be completed in 2 turns, which don't have to be in a row. After the [[Gemstone Hoarder]] and [[Play Dead]] loop is completed, you can just wait for any deathrattle minion and [[Confront the Tol'vir]] which will end the game. Honestly, this combo is fun to pop up.
On the negative side, this deck is solitaire. Since it has only 1 win condition, the gameplay loop is the same against almost every opponent. Also, it has 0 survivability. That is the reason why the win rate is higher when going first: your opponent has 1 less turn to hit you before you have enough mana for the combo.
Particularly, this deck feels like another version of the 30-card Boarlock (not my favorite strategy); my attempt to create a 40-card version was unsuccessful. So, if anyone comes up with a 40-card playable version, pls share it!