Athame Artis is a 5 star Sword obtained from Weapon Event Wishes in Genshin Impact 6.2.

CRIT DMG from Elemental Bursts is increased by 16% / 20% / 24% / 28% / 32% . When an Elemental Burst hits an opponent, gain the Blade of the Daylight Hours effect: ATK is increased by 20% / 25% / 30% / 35% / 40% . Nearby active party members other than the equipping character have their ATK increased by 16% / 20% / 24% / 28% / 32% for 3s.
Additionally, when the party possesses Hexerei: Secret Rite effects, the effects of Blade of the Daylight Hours are increased by an additional 75%. This effect can be triggered even if the equipping character is off-field.