Fate involves defeating "Hungry Harpuia" who are attacking a group of 5 "First generation Monoceros" creatures.
Fate text tracks "Hungry harpuai defeated 5/5" but this is incorrect.
The progress bar % for this fate is tracking how many Hagry Harpuia are defeated.
The 5/5 appears to track how many "First generation Monoceros" are still alive.