In Theros block, we are told, there are to be five allied-color multicolor gods as well as five enemy-color ones. One member of the former group was actually the first of the minor gods we knew about; Karametra's Acolyte was revealed early on as the Holiday Gift Box promo for this year (and it features a Golden Apples of the Hesperides-like alternate art). In addition, Karametra was mentioned in the Planeswalker's Guide to Theros, Part 1, which otherwise focused solely on the major gods whose cards were printed in the first set of the block.
In the time that has passed since then, we have come to learn that Karametra is the green and white God of Agriculture, or essentially the Theros equivalent of ancient Greece's Demeter (or Ceres, in Latin). Her primary worshipers come from Setessa, which, among the three major poleis, has the greatest connection to nature, being located in the deep woods. Although she is known to have some enmity with Nylea, who views farming as a corruption of nature, the acolytes of Karametra see no conflict with revering natural forces and imposing mortal will upon the earth. As the flavor text of Karametra's Acolyte says:
"The wilds are a garden tended by divine hands."
No matter what Nylea's worshipers say, Karametra is not necessarily pacifistic or "soft" despite her benevolence and civilized exterior. The Setessan Battle Priests pay homage to Karametra:
"Your god teaches you only how to kill. Karametra teaches me to defend what I hold dear. That is why I will prevail."
In addition, Karametra is apparently adept at animation magic, bringing the inanimate to wrathful life. She has been known to do this with Bronze Sables:
The Champion stood alone between the horde of the Returned and the shrine to Karametra, cutting down scores among hundreds. She would have been overcome if not for the aid of the temple guardians whom Karametra awakened. - The Theriad
In terms of the other gods in Nyx, Karametra has an aforementioned unusually high level of conflict with Nylea, with whom she shares a color in her alignment, but probably has favorable relationships with Heliod and Ephara.