The waverider, the other water themed frame, beaten by a random Grineer henchman in her own lore entry - Yareli!

Release date: 2021-07-06

Passive: Everflowing with the seas, whenever Yareli moves for at least 1.5 seconds, she gains the Critical Flow buff that increases Critical Chance on her secondary Weapon by 200%.
Sea Snares - Form three water globules that seek out enemies and expand on contact, simultaneously damaging and immobilizing their victims.
Merulina - Summon Merulina, a rideable creature of the waves, and the inspiration for K-Driving. Merulina protects Yareli by absorbing a large portion of incoming damage.
Aquablades - Tear through foes with a trio of orbiting aquatic blades.
Riptide - Drag enemies into a crushing maelstrom and then blow them away in a watery burst. Each enemy trapped in the vortex increases the burst’s Damage.

Acquisition: Main blueprint is acquired by completing The Waverider quest. Component blueprints are acquired through Research inside the Ventkids’ Bash Lab within the Clan Dojo.