Gorm the Great is a good-ol' Lure creature
In my opinion the key buff Slivers are: Sinew Sliver, Sedge Sliver, Predatory Sliver, Muscle Sliver, Megantic Sliver, Cleaving Sliver, and Bonescythe Sliver
Perhaps more critically for the Doctor Who cards, however, is the interesting trend of other cards giving other cards Suspend
This deck is weak to countermagic and similar interaction Game 1, so it makes a lot of sense to transform into the older creature/planeswalker plan, and I believe Glorybringer to be a great way to facilitate playing fair. Creatures (17) 2 Ayli, Eternal Pilgrim 2 Archangel Avacyn 4 Thraben Inspector 2 Thalia, Heretic Cathar 3 Sram, Senior Edificer 4 Walking Ballista Planeswalkers (4) Lands (24) Spells (15) Probably my most boring deck today, but I think it showcases a valuable lesson

Biggest Omissions: Sliver Legion $39.99 Glimpse the Unthinkable $34.99 Tezzeret, Agent of Bolas $21.99 Fulminator Mage $19.99 Maelstrom Pulse $17.99 Gaddock Teeg $17.99 Huntmaster of the Fells $9.99 Kitchen Finks $9.99 Nicol Bolas, Planeswalker $8.99 Knight of the Reliquary $8.99 Lightning Helix $5.99 Boros Charm $1.99 Fulminator Mage would have been nice, but it was just printed in Modern Masters 2015 , and (Tarmogoyf excepted) it seems like WotC has been good about not printing the key cards from one Masters set directly in the next
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