just wanted to share a deck that I've had tons of fun with and currently have 85% win rate (17-3) with (truth be told it is lower ranks 20-15), but I've faced spell hunters and odd paladins and all those OP things and this deck had no trouble at all if played correctly) .
The only card that I don't have which I would've added is Zilliax but I'm currently trying to craft it so I'll post an update after I've added it.
I'll post a detailed guide at 15 likes.
First of all thank you to everyone who commented and gave some info back and some insight.
I've made some changes to the deck to amend for a bit harder decks at rank 4 where I'm currently at. There is a very big amount of Kingsbane rogues, Spell hunters and Mecha'thun priests so you can tweak your deck accordingly depending on what you face. I'm pretty sure I'll reach Legend with this in a next couple of days.
Also a huge shoutout to the people who showcased the deck on Youtube!
Your aim for most openers is to play Cavern Shinyfinder on turn 2, followed by Necrium Blade on turn 3 to clear a minion on board if possible or go face, and then use the weapon to proc Devilsaur Egg on turn 4. This deck usually explodes at turn 5 and 6 due to the fact that you can drop a Mechanical Whelp and proc it with your weapon, giving your oppponent a 7/7 to clear and a danger of leaving Mechanical Whelp alive for you to play Necrium Vial on it next turn (if that happens most of your opponents will concede the turn after unless they can clear the board).
One key thing to understand is how Da Undatakah works. He can copy a deathrattle of the same minion multiple times. Meaning that if 3 of your Mechanical Whelps died, he will copy the deathrattle three times and not just once.
Also, you have to understand that when you use Carnivorous Cube on Da Undatakah , when the Carnivorous Cube dies it will summon two REGULAR 8/5 Da UndatakahS WITH NO DEATHRATTLE ON THEM. That's because he gains them with a Battlecry, and not a board summon.
Also it's very important to assess every possible situation when it's your turn and you have a good board. Sometimes the decision between going face and trading can cost you the game because you might lose tempo with trading, and you might've been better off with going face and letting the enemy deal with your board. Knowing when to trade is something you learn with experience and can't be explained in a guide. Think of what deck your opponent is playing, what he might have in hand, and try to predicit his next turn.
I've been asked about some other deathrattle cards as addition to the deck, however the key strength of this deck is the big minions you spawn from these deathrattles, so adding cards like Bloodmage Thalnos or Gral, the Shark will only slow you down
For those of you who have more dust or cards to spare, there is also a way more pricier version of Deathrattle rogue that I would personally want to try but can't.
This is the deck: https://www.hearthstonetopdecks.com/decks/deathrattle-rogue-featuring-da-undatakah/
In case any of you try it out let me know how it goes ^^