Boros Energy is full of free or cheap aggressive threats and interaction, but Vexing Bauble only counters spells cast with no mana spent — this hits essentially nothing in their maindeck here (no Mishra's Bauble, Mox Opal, or similar zero-cost spells in their list), so keep it on the bench against the 75 shown and only board it in as a hedge if you actually see something free. The real plan is surviving their fast clock: extra Dismember lets you remove Ragavan, Nimble Pilferer or Ocelot Pride cheaply before they snowball energy and tokens. Cut the top-heavy Nulldrifter and two Sowing Mycospawn since this game is about stabilizing the board quickly, not grinding extra value, and you need to assemble the combo before they overwhelm you with go-wide pressure from Guide of Souls and Voice of Victory.