I believe he has Pot of benevolence to be able to add cards to either deck in case he needs before hitting 0 cards, abyssal is just to lower his health and hope to reach in the end 100 life points
i have abyssal just to drop my life points to make it 100 life points and pot for many uses like if he negates one of my cerb or just to boost more my monsters or even to work my life points to make it 100 very good card.
Anoymous
Bakura