Where it struggles is with a lack of artifacts and enchantments, and 40 total lands that feel a little overkill, especially when you could find other ways to produce mana if needed
I havent been super impressed with Ancient Tomb
Thanks to X-drop creatures, even the one-mana requirement is a bit misleading
Legendary Creature - Demon Kozilek's Unsealing Devoid (This card has no color.) Whenever you cast a creature spell with mana value 4, 5, or 6, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this token: Add ." Whenever you cast a creature spell with mana value 7 or greater, draw three cards
Convention Exclusives: Cards available only at specific events like MagicCon or through convention-exclusive bundles
As for reprints, we have the ever-valuable Urza's Incubator, a powerful cost reducer for typal decks