The Phoviverse is written in a strange chronological order, by which I mean that a story happens basically on the date that it was published, unless specified otherwise, or set in alternate/parallel settings (e.g. fanfiction stories tagged under Alternate Worlds). The latest stories are always available on the sidebar.
The original universe was MK3, and mostly followed the adventures of Arkay, occasionally spiraling off to follow other members of his family. Most of MK3 can be disregarded (it’s not the best) but Battle of Brothers is the final story arc of MK3 and leads in to MK4. The only real required reading is Death’s Deal, Not Such A Good Deal, The Dark Alley, and Priming, which explain how Arkay became an immortal being in servitude to Kinisis.
After MK3, the old Phoviverse was abandoned and Kinisis made a new universe, the MK4 Phoviverse, with Kenon as her husband and four deities serving her. Kairos (the old Time Dragon), Epani, Yisini and Arkadin (the now deified Arkay) all work hard but have their conflicts between each other.
At some point, the MK4 universe was somewhat shattered in an invasion of black and gold. The story split into three plot points: The Union of All, where Kenon, Epani and Yisini tried to fix the mess Kinisis made, Twelve Guardians, which features Kinisis’s adventures with her twelve perfect servants, and the Travels of the Thantir, following what Retvik and Arkay did after being kicked out of the universe.
However, Kinisis eventually becomes a tyrant, which spurs the events of the Doom Drums. This story brings the MK4 universe to a close, but denizens of the MK4 universe, that were trapped outside it, continue to exist as within Travels of the Thantir.
The current universe is MK5. This universe is basically a rebuilt and rewritten MK4 universe, but made smaller and a billion times better. The initial story line is Thantoamnesia, which introduces the new mortal protagonists, and their adventures are chronicled under Dessaron Adventures. The Travels of the Thantir continue throughout the MK5 timeline, under the Thantir tag.
However, a major event, Ftora Olon, has shaken up the MK5 universe, altering history, severing two deities and forcing the creation of lesser deities in Spirits Anew. MK5 continues still, split into the ongoing various Thantir story arcs, and the Twelve Spirits story lines, which follow the new deities.