Splendor of Tranquil Waters is a 5 star Sword obtained from Weapon Event Wishes in Genshin Impact 4.2.

When the equipping character’s current HP increases or decreases, Elemental Skill DMG dealt will be increased by 8%/10%/12%/14%/16% for 6s. Max 3 stacks. This effect can be triggered once every 0.2s. When other party members’ current HP increases or decreases, the equipping character’s Max HP will be increased by 12%/15%/18%/21%/24% for 6s. Max 2 stacks. This effect can be triggered once every 0.2s, and can be triggered even if the wielder is off-field.