Eldrazi Tron is almost entirely colorless spells — Thought-Knot Seer, Devourer of Destiny, Kozilek's Command, Mind Stone, Karn, the Great Creator, and Ugin, Eye of the Storms — making Consign to Memory an outstanding one-mana counterspell that can stop nearly anything they cast. White Orchid Phantom devastates their manabase by destroying an Urza's Mine, Urza's Power Plant, Urza's Tower, or Eldrazi Temple, which are all nonbasic and often irreplaceable for hitting their colorless-heavy curve, while also providing an evasive clock. Thoughtseize is weaker since Tron decks are resilient with redundant mana sources and card selection from Expedition Map, so trim it along with some Faithful Mending. Solitude stays in as your best answer to a Thought-Knot Seer that resolves, while Prismatic Ending handles lower-cost permanents like Glaring Fleshraker.