Grixis Control is heavily blue, so Pyroblast and Red Elemental Blast are excellent against Counterspell, Preordain, Lorien Revealed, Brainstorm, Spell Pierce, and the artifact creature Baleful Strix, protecting our burn spells and removing their card advantage engines. This lets us fight through their permission suite while racing their removal (Snuff Out, Cut Down, Cast Down). Cut the slower value cards like Highway Robbery and Melded Moxite since we need proactive, protected threats rather than grindy card advantage against a deck built to grind longer games with Thorn of the Black Rose and Murmuring Mystic.