Sliver Overlord and Sliver Queen are both excellent additions to the deck, but they don't particularly benefit from Gravemother's encore ability
She has a pretty high cost of 5 Ink (which can be reduced to 3 with Shift), along with 4 each of Strength and Willpower, plus 2 Lore
Pokemon Horsea - 031/101 (Delta Species) Dragon Frontiers Uncommon Market Price $1.51 $0.10 Median $1.51 Normal $1.51 Reverse Holofoil $34.00 Prices from TCGplayer, updated 5 hours ago
There are other ways to draw a lot of cards with white, but I'm partial to the enchantress strategy, which in my opinion is some of the best card draw in the game, let alone for mono-white decks
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