Sonic Assault

Tapping a creature is rarely worth a card by itself: it removes a blocker or a single attacker for one turn, and combat tricks that cost less do the same work. The trick is the second clause, which turns this into a Falter effect with a clock attached. Two damage to the creature's controller every time you point it at a board reframes the spell as reach masquerading as utility. Jump-start is what closes the loop: the first cast and the graveyard recast each fire the two-point burn, so a single copy can deal four to the face across two turns while clearing the way twice for an attack. That is the structural argument for aggressive blue-red tempo, where the tap matters when you are racing and the burn matters when you are not. The discard on the recast is the price that keeps the loop honest: pulling the card back from the graveyard costs a resource, so the second cast asks you to trade a card in hand for another swing and another two points, a bargain an aggressive deck will usually take when it is short on gas but ahead on the board. Neither half is dead weight, which is the whole reason the two-color slot earns its cost: the racing player and the reaching player are the same deck, and this pays both of them at once.