Blue Elemental Blast

The original color-hoser, and the cleanest expression of the design philosophy Alpha was willing to commit to: hate cards that were free wins against one color and dead cards against the other four. The modal split is what gives it its teeth. One mana to counter a red spell on the stack, or one mana to destroy a red permanent already on the battlefield, means a single card answers both halves of red's plan (the burn pointed at your face and the Shivan Dragon already in play), with the timing flexibility to wait until red has committed before deciding which mode matters. The decades since have been a slow retreat from this template. Prevention-based answers softened the punishment to a tax on damage rather than a flat denial. Hydroblast kept the exact same two modes but loosened the casting requirement, letting it target any spell or permanent (it only bites when the target is red on resolution), where Blue Elemental Blast demands a red target to be cast at all. Later one-mana hosers narrowed the scope, raised the cost, or both, because a sideboard card that is simultaneously a hard counter and a Naturalize for one mana sets a ceiling that warps every red card priced against the possibility of it. The card itself has stayed legal in eternal formats wide enough to absorb a perfect answer to one color; what it represents (the unbounded, unconditional, mana-cheap hoser) is a design lever the company has chosen not to pull again.