Ended a PvP battle, got this after the victory screen (before the rewards I believe)
I was returned to the world map afterward. Battle counted as a victory, as it should had.
Since I browsed World.json before it was encrypted, I would say these 4 numbers are supposed to be IDs of cards, and the 3rd and 4th one seems odd to me. Unfortunately, I don’t remember what was the team I battled against…