Dimir Tempo is entirely blue-based with Force of Will, Daze, Brainstorm, and Ponder, making Pyroblast a premium answer that counters their countermagic or destroys a resolved Murktide Regent or Tamiyo. Chrome Mox exposes cards to Thoughtseize and is a liability against Wasteland pressure, so trimming it for reactive power is correct. The extra Eldrazi Confluence adds another flexible answer to shrink Murktide Regent or reset Tamiyo. Keep Chalice of the Void at one and Trinisphere mainboarded since they devastate the opponent's one-mana cantrip and discard suite.