Yes, this is a very expensive deck.  I have the cards, so i use them.  Parallel optimization for constant incremental advantage, and grinding disadvantage against all opponents.  Any given card is carefully chosen so that in combination with any other card, a mild advantage has been generated. None of the individual pieces are absolutely vital other than the final combo.  The final combo is not necessary to win, I just think it's elegant.  It consists of Teysa, Orzhov Scion plus Darkest Hour plus Blasting Station.  Teysa triggers whenever a black creature is put into my graveyard by generating a white 1/1 flying spirit creature token.  Darkest Hour in play makes the token black, creating an endless creature token loop ensuring that whenever one of those tokens die, it's replaced by another.  Adding Blasting Station allows the use those tokens for infinite damage to any target.

Each other card in this deck is chosen to help achieve this goal.

(Further explanation to follow.)