Sunny Blast, a unicorn who lives in Canterlot, is suddenly sent to a different dimension called Azeroth, with only three colors of ponies. She gets send to the Herd, the faction that has an eternal war against the Alliance.

Kich, on the other side, is originally from the Herd, and she gets suddenly sent to a different dimension which happens to be Equestria.
Read as the ponies get used to the new cultures and all the experiences they have as they are teleported to different dimensions.