Kiora venerates the huge monsters of the sea, such as the leviathans, krakens and other denizens of the inky depths. For her these creatures embody the ability to withstand any persistent force: time, water, predation and darkness. She seems calm and wise, but her dreams are as bizarre and alien as the depths from which her creatures rise.
After the Eldrazi began to roam free on Zendikar, Kiora fled, seeking some way to raise enough power to defeat them, believing once more that the masters of the depths are the only creatures strong enough to repel the aetheric parasites. She has traveled from world to world, harnessing the powers of the oceans and gathering as many of its inhabitants to her as possible. In her travels, she made landfall on the shores of Theros and immediately called a gigantic tsunami to her, hoping to attract the attentions of the deep dwellers. It struck the polis of Meletis and caused untold destruction, but she had little concern, only caring if her beacon had been answered. In some ways, it was successful, but it also attracted the Tritons, Theros's native merfolk. They believed Kiora to be an avatar of Thassa and she did little to dissuade them of that opinion, secretly enjoying the attention.
Journey into Nyx
Trading on local legends, she created one for herself, borrowing identities as needed as she amassed power. One such facade she adopted was that of Callephe, the legendary mariner said to have sailed into Nyx itself. It was this lie that brought her path across that of Ajani Goldmane and Elspeth Tirel. The pair sought out Callephe for her skills, trusting her able to bring them to the Temple of Mystery, the ancient tree at the edge of the world.
Kiora agreed to do so, but for purposes she wasn't forthcoming about, dismissing it with a wall of good cheer. She led them along for the ride as she pursued her own agenda, never letting it slip that she was not who she said she was. The truth finally came out shortly after they set off, as Kiora brought them to the sunken city of Arixmethes. It was no city at all, in truth, but a massive kraken upon whom a city had been built. The god Thassa would not allow Kiora to take the beast from her, but first assisted Elspeth and Ajani in their journey.
The pair taken care of, Thassa turned her attentions to Kiora. After a fight involving many sea monsters and kraken (some of them summoned from other planes), Kiora escaped mostly unharmed and clutching Thassa's magical bident Dekella. 
Quoted or referred to:
- Kiora was originally named "Kiora Atua." Parallels were drawn with the Maori, because in Maori, "Kia ora" is a greeting (meaning "be well") and Atua is the Maori word for "god" or other similar terms such as "ancestor" or "spirit". However, this connection between the planeswalker and the Maori was not intentional. In January 2014, it was announced that "Atua" would be dropped from her name as it was considered inappropriate and offensive by Wizards, as it disrespectfully treads on sincere beliefs. As it stands, Kiora has no official last name. However, the name briefly reappeared on the box of her Funk Pop! Vinyl Figure. 
- The artwork on Kiora, the Crashing Wave references the classic woodcut The Great Wave off Kanagawa by Hokusai.
- Doug Beyer. (May 25, 2011.) "The Grand Mana Tour", Daily MTG, magicthegathering.com, Wizards of the Coast.
- The Magic Creative Team. (January 08, 2014.) "Planeswalker's Guide to Born of the Gods", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Kelly Digges. (February 12, 2014.) "Kiora's Followers", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Kelly Digges. (May 20, 2015.) "Drop for Drop", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Mike McArtor. (March 12, 2014.) "Kiora Package", Daily MTG, magicthegathering.com, Wizards of the Coast.
- Doug Beyer. (January 15, 2014.) "Why "Kiora, the Crashing Wave" and not "Kiora Atua"", A Voice for Vorthos, Tumblr.
- Mark Rosewater. (January 22, 2014.) "Is the BNG planeswalker still called "Kiora Atua?"", Blogatog, Tumblr.
- Mike McArtor. (February 4, 2015.) "Funko Pop! Planeswalkers, Part Deux", Daily MTG, magicthegathering.com, Wizards of the Coast.