Thraben Charm scales with your creature count and can snipe Delver of Secrets or a cheaply-cast Tolarian Terror/Cryptic Serpent, while its graveyard-exile mode denies the self-mill density (Thought Scour, Mental Note) that discounts those Serpents. Mana Tithe punishes a deck that's often tapped low holding up Counterspell, letting your threats or answers resolve uncontested. Clowning Around's fragile tokens and the lone Guardians' Pledge are too slow against an efficient tempo-permission deck, so they're cut along with two Salt Road Packbeast, whose affinity discount matters less when racing a faster, cheaper blue clock. Neither Pyroblast nor Blue Elemental Blast are in our sideboard, so this plan leans on Thraben Charm and Mana Tithe for interaction instead.