Who Counters Challenger Dominiel in Epic Seven?

Shepherd of the Dark Diene, Frieren, Briar Witch Iseria and other hard counters counter Challenger Dominiel. Her value is the crit-damage and attack buffs she hands out; an enemy who strips, steals, or shortens those buffs erases the window she opens, leaving the team with no amplified burst.

Cleanse and buff removal: Her value is the crit-damage and attack buffs she hands out; an enemy who strips, steals, or shortens those buffs erases the window she opens, leaving the team with no amplified burst. Immunity and buff-block: If foes apply immunity before she acts, her crit-damage buff and Combat Readiness support fail to take hold, and she has no debuff pressure to fall back on. Spread-out lineups: Electrocute only strikes one enemy and rewards critical hits rather than clearing waves, so against multiple targets she cannot threaten the back line or finish on her own. Burst-down and turn denial: As a slow Mage with light defenses she relies on going early and on spending her stacked-attack passive with an attack; rush her down or deny her the opening turn and her contribution collapses.

Crit-reliant teams needing a fast kickstart: Supercharge gives every ally bonus Critical Hit Damage for 3 turns and pushes the team's turn gauge forward, then hands Dominiel an extra turn, front-loading a burst window before slower compositions can set up. Damage dealers who can't crit reliably: Her passive keeps her own Critical Hit Chance high and the team-wide crit damage buff turns crits into much larger hits, lifting carries that otherwise whiff or roll low damage. Enemies that fold to a stacked opening: The Combat Readiness push plus her extra turn chains the team into burst quickly, and her Attack climbs each time an ally crits first, so the opening swing lands amplified.