Mulligans
1st step: make a inmortal Undatakah (gain the Deathrattle of Immortal Prelate first and after the Deathrattle of Silver Vanguard, the Deathrattle of Primaflin Champion isn’t important the place)
Then, you play Sunfury Protector, so, you have a 8/5 Taunt minion with “Deathrattle: resummon this”
(Never play Silver Vanguard with Undatakah in the deck; if you fail the Undatakah’s battlecry, it shuffled in the deck when die, so you can try again without do anything special)
2nd step: All the spell you cast in your Undatakah comeback to you hand when it die, so, the next turn you play a successful Undatakah, you play 2 Blessed Champion in it, having a 32/5 infinite taunt minion in board
3rd step: when it die, it return the 2 Blessed Champion to your hand, so you can cast it again, making a 128/5 infinite minion with “DR: Return 4 Blessed Champion to you hand)
And you repeat this the times you wish, you burn a lot of cards because your hand always be full with Blessed Champions, but is the only you need. You can have a 131072/5 so easy
(If your oponent silence or transform your Undatakah, make a very great play: “Esc + Concede)