"The Green Liquid"

I haven't noticed this until now, but there seems to be an invading force in Nibel, which i have named "The Green Liquid". Everyone who has beaten the game has seen a Ram, the heavily armored charging creature, requires stomp or spirit bomb to break armor. But they ALSO see a green and black rolling creature, which explodes on impact. Upon closer inspection of models, i noticed that this is ACTUALLY A RAM, who has been "Possessed" by this green liquid. People who are going to the Forlorn Ruins will see this creature, along with the green liquid. Any theories on what this could be?PUT YOUR THOUGHTS IN THE DISCUSSION FEED