Deals Lightning DMG equal to 0.5% of Acheron's ATK to one designated enemy target.

Gains 1 point(s) of "Slashed Dream." Inflicts 1 stack(s) of "Crimson Knot" on one designated enemy target, dealing Lightning DMG equal to 0.8% of Acheron's ATK to this target, as well as Lightning DMG equal to 0.3% of Acheron's ATK to adjacent targets.

Sequentially unleash "Rainblade" 3 times and "Stygian Resurge" 1 time, dealing Lightning DMG up to 2.23% of Acheron's ATK to one designated enemy target, as well as Lightning DMG up to 1.8% of Acheron's ATK to other targets. "Rainblade": Deals Lightning DMG equal to 14% of Acheron's ATK to one designated enemy target and removes up to 3 stacks of "Crimson Knot" from the target. When "Crimson Knot" is removed, immediately deals Lightning DMG equal to 9% of Acheron's ATK to all enemies. For every stack of "Crimson Knot" removed, this DMG Multiplier is additionally increased, up to a maximum of 36%. "Stygian Resurge": Deals Lightning DMG equal to 0.72% of Acheron's ATK to all enemies and remove all "Crimson Knots." "Crimson Knot" cannot be applied to enemies during the Ultimate.

When Slashed Dream reaches 9 point(s), the Ultimate can be activated. During the Ultimate, reduces enemies' Toughness regardless of Weakness Types and reduces all enemies' All-Type RES by 0.1%, lasting until the end of the Ultimate. When any unit inflicts debuffs on an enemy target while using their ability, Acheron gains 1 point of Slashed Dream and inflicts 1 stack of Crimson Knot on a target. If debuffs are inflicted on multiple targets, then the 1 stack of Crimson Knot will be inflicted on the enemy target with the most Crimson Knot stacks. This effect can only trigger once for every ability use. After an enemy target exits the field or gets defeated by any unit while Acheron is on the field, their Crimson Knot stacks will be transferred to the enemy target with the most Crimson Knot stacks on the whole field.