Acheron 
Nihility A drifter claiming to be a Galaxy Ranger. Her true name is unknown. She walks the cosmos alone, carrying with her a long sword.
HP
ATK
DEF
SPEEDNihility Dps Build
Best Light Cone
Acheron Best Stats
Acheron Best Substats
Acheron Best Relics
Acheron Best Ornaments
Izumo Gensei and Takama Divine Realm
Firmament Frontline: Glamoth
Inert Salsotto
Acheron Best Teams
F2P Debuff Team
For a F2P team, you can use Acheron with Mortenax Blade and Welt. Both of them apply enough debuffs to consistently stack up Acheron's Ultimate. Mortenax Blade also boosts the Ultimate DMG of the whole team, along with a general DMG amp. Welt brings DEF shred and delays the enemy's turns. Permansor Terrae acts as the sustain character of the team, providing ATK to Acheron and shields for the team.
Beginner Team
For beginners who don't have any limited 4-Star or 5-Star characters yet, Asta and the Fire Trailblazer can debuff the enemy through Burn and Taunt respectively. The Fire Trailblazer can equip the Trend of the Universal Market to apply Burn on enemies. Since Acheron's kit becomes stronger when Nihility units are in the party, we recommend replacing your Supports as soon as you get debuffers.
Best E0-E1 Team
Acheron's best team at Eidolon 0 and 1 consists of two other Nihility units to max out the DMG buff from her Bonus Ability. Mortenax Blade and Cipher can debuff the enemies on their turn to add stacks for Acheron's Slashed Dream. Cipher can equip Lies Dance on the Breeze or Resolution Shines As Pearls of Sweat to have more chances of applying debuffs on an enemy. Mortenax Blade boosts Acheron's Ultimate Damage and gives her a general DMG amp, along with DEF shred to enemies for even more damage. You can run the team either sustainless or with a sustain character, as both compositions are viable. Sustainless teams are better with Welt since he can delay enemies and bring even more debuffs to the fight.
E2 Hypercarry Team
If you unlocked Acheron's 2nd Eidolon, you can replace your second Nihility unit with a hypercarry support and still activate the full DMG buff from Acheron's Bonus Ability.
Skills
Deals Lightning DMG equal to #1[i]% of Acheron's ATK to one designated enemy target.
Gains #3[i] point(s) of "Slashed Dream." Inflicts #3[i] stack(s) of "Crimson Knot" on one designated enemy target, dealing Lightning DMG equal to #1[i]% of Acheron's ATK to this target, as well as Lightning DMG equal to #2[i]% of Acheron's ATK to adjacent targets.
Sequentially unleash "Rainblade" 3 times and "Stygian Resurge" 1 time, dealing Lightning DMG up to #6[i]% of Acheron's ATK to one designated enemy target, as well as Lightning DMG up to #7[i]% of Acheron's ATK to other targets. "Rainblade": Deals Lightning DMG equal to #1[f1]% 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 #2[f1]% 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 #5[f1]%. "Stygian Resurge": Deals Lightning DMG equal to #3[i]% 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 #1[i] 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 #2[i]%, 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.
Traces
Eidolon
When dealing DMG to debuffed enemies, increases CRIT Rate by
Debuffs are negative status effects that render units weaker. Unless otherwise specified, debuffs can be dispelled.
The number of Nihility characters required for the Trace "The Abyss" to achieve its highest possible effect is reduced by 1. When this unit's turn starts, gains 1 point of Slashed Dream and inflicts 1 stack of Crimson Knot on the enemy with the most Crimson Knot stacks.
Ultimate Lv. +2, up to a maximum of Lv.
When enemy targets enter combat, inflicts them with the Ultimate DMG Vulnerability, increasing the amount of Ultimate DMG they take by
Skill Lv. +2, up to a maximum of Lv.
Increases the All-Type RES PEN for the Ultimate DMG dealt by Acheron by
When dealing DMG, ignore a part of the enemy target's resistance to the corresponding damage type.