Mono-White Initiative leans on Chalice of the Void set to X=0 or X=1 to lock out cheap spells, plus Thalia and Archon of Emeria to tax and restrict your casting, making this a very difficult matchup for a combo-heavy deck. Disruptor Flute can name a problematic spell like Archon of Emeria or Chalice of the Void to tax its casting cost by {3}, while Abrade destroys Chalice of the Void or Chrome Mox outright. Brotherhood's End sweeps their small creatures like Thalia, Anointed Peacekeeper, and Archon of Emeria, or blows up their Chalice of the Void and other cheap artifacts. City of Traitors is a poor fit here since it dies to Wasteland, and Flusterstorm has no legal targets against their creature-heavy plan.