The Fip people worship the God of War. In return, He has allowed them to conquer not just their continent, but Challen and other parts of the world as well. The Fip Dynasty generally allows the conquered countries to continue following their customs and worshiping their local gods in exchange for tribute. However, a member of the Fip family serves as a monarch for each country, and they're all subordinate to the emperor in Fip itself.
Fifth Season is the title of Book Four in the series. (I chose that title long before N.K Jemsin's The Fifth Season came out, and since titles can't be copyrighted, I decided to keep it.) It's told through the point of view of Ysabel, the Fall Avatar. "Fifth Season" refers to the way Kron becomes involved with the Season Avatars, even though he's not one of them and has a different type of magic. While Ysabel's quartet appreciates his help, the older quartet doesn't. One of them tells Ysabel, "Challen doesn't need a fifth season." Here's the blurb:
Ysabel became the Goddess of Fall’s Avatar to care for animals, but her kind heart may prove fatal to her loved ones.
When a pair of strange animals, part bird and part lizard, invade the country of Challen during a magical weather storm, Ysabel must learn if they’re ordinary creatures or if they’re connected to Salth, the Season Avatars’ sworn enemy. However, the clawfeet are resistant to her magic.
After tragedy strikes the Avatars, Ysabel comes up with a desperate plan to allow all twelve of them to face Salth together as required by the Four Gods and Goddesses of Challen. Jealousy, however, tears an ally from the Avatars during their most vulnerable time as even more beasts rise against them. If Ysabel cannot control the strange animals and use justice as well as mercy, she will not only lose her position as Avatar but the people she loves.