Flamescroll Celebrant // Revel in Silence

Your opponents can't cast spells or activate planeswalkers' loyalty abilities this turn.
Exile Revel in Silence.

Whenever an opponent activates an ability that isn't a mana ability, Flamescroll Celebrant deals 1 damage to that player.
{1}{R}: Flamescroll Celebrant gets +2/+0 until end of turn.

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Activated abilities contain a colon and appear in the form “[Cost]: [Effect].” Some keywords (such as equip) are activated abilities and will have colons in their reminder texts. Loyalty abilities of planeswalkers are also activated abilities.

An activated ability that costs mana to activate is not a “mana ability” unless it could also produce mana and has no targets.

Casting Revel in Silence in response to a spell or ability won’t affect that spell or ability. That is, it’s not countermagic.