Disallow

The lineage runs from Counterspell to Cancel: two mana of double blue, three mana of double blue, the same answer at a steadily worse rate. What pays for the extra mana here is the third clause. Counterspells answer spells; this one also answers activated and triggered abilities, the category of effect that has historically slipped past the counter wall entirely. A creature already resolved and now using an activated ability, a planeswalker ultimate going on the stack, an enters-the-battlefield trigger, a fetchland's sacrifice payoff: all of these are abilities, not spells, and a Counterspell sits there inert while they happen. Stifle does that job for one mana but cannot touch a spell; this card collapses both functions into one instant. The single carve-out is mana abilities, whether activated or triggered, and it is a deliberate one: those resolve without ever using the stack, so nothing can target them, and a counter that could deny mana production outright would warp every interaction at the cost of a single card. The result is a Swiss-army counterspell that buys breadth with mana. It answers the things other counters cannot: the loyalty ability that would otherwise resolve unopposed, the sacrifice trigger that fetches a game-ending payoff, the artifact tapping for a combo activation. What it surrenders is the rate. A full mana over the genre standard is the price of pointing at the stack's entire contents rather than just its spells.