Mana-Fixing Artifacts Cultivate, Farskeek, and both Manaweft and Gemhide Slivers help with Sliver Swarm's mana problems, but they're all contingent on drawing a green source of mana in your opening hand
The deck also included the first reprint of Crawlspace, an artifact from Urzas Legacy
Not to mention, with Naveens Its Beautiful No
She can grow out of control with little effort, and is a well-respected threat by herself
Changing the Reserved List While the anti-Reserved List crowd tends to have the misconception that the Reserved List was an outright mistake, rather than a shortsighted solution to a very real problem that could have killed the game two decades ago, the proReserved List crowd as a misconception of its own: that the Reserved List is unchanging and that Wizards has held to its promises for the past 25 years
Thoughtseize gives the user an insight on the most likely play patterns for the upcoming turns, and can be used proactively to either discard an answer to a threat, disrupt the opponents curve, or strip a vital combo piece out of the opponents hand