Ruby Storm needs to chain cheap red rituals and cantrips (Desperate Ritual, Seething Song, Manamorphose) to assemble a storm count, so Hydroblast is premium interaction that can counter a key ritual or burn spell at instant speed for one mana, disrupting their whole turn. Steel Sabotage can answer their few artifact-based mana sources if relevant, but more importantly provides cheap flexible interaction. Cut the clunky Giant's Boulder, Bender's Waterskin, and Extract a Confession since they're too slow and don't interact with the combo plan; this matchup is about countering their key enabler before they go off, so prioritize cheap, efficient interaction over card advantage.