10 Sacrifice The most popular build for Muldrotha, the Gravetide, sacrifice decks does exactly that: sacrifice cards to build a graveyard for her to pull from
The first will force the targeted foe to draw three and discard three at random (good for discard punishing decks like Megrim), sacrifices a non-token artifact (not a Treasure, Clue, Blood, or Food), and the Balor shoots them for the damage to the cards in their hand (nice)
Knight-Errant is the backbone of this strategy and the namesake of the deck as it allows you to continue refilling your hand with threats while also making use of your tokens as mana sinks
You may put one of those cards back on top of your library
its relatively normal to see these three spells in the one deck, as they can help improve consistency while keeping your hand stocked
It doesnt count It does count, because the most expensive version of this card was released in Phyrexia: All Will Be One Collector packs