Involuntary Cooldown
Tapping something down is the weakest form of removal in the game: it buys a single turn and hands the permanent right back. Stun counters rewrite that math. The mechanic works by intercepting the untap step, spending a counter to keep the permanent tapped instead of freeing it, so two counters means two turns of forced dormancy per target. Doubling the count here turns a fleeting Frost Breath into something closer to a soft Pacifism that also hits artifacts: a mana rock, a vehicle, a big blocker, two of them at once. What keeps it in check is that stun counters only spend themselves when the permanent would untap, so anything that never needed to untap (a summoning-sick creature that stays back) shrugs off the effect, and the target is still a live permanent the whole time, not exiled or shrunk. The sorcery speed matters too: this cannot ambush an attacker mid-combat or blank a blocker on the crack-back. It is a proactive tempo play, cast on your own turn to strip two threats out of the opponent's next two attack steps. As a piece of the stun-counter design language, it is the color's clearest statement that blue's answer to permanents is not destruction but detention, applied twice over.
