User blog comment:Lord Loss/Monster Appreciation Week: Green Nargacuga/@comment-5020152-20130617123537/@comment-84.229.207.35-20130618141842

I think Green Nargacuga's ability to change color is limited to shades of green, it's tail spikes can stun because they are shot with more force which strains it's tail muscles and that is why it's tail tip is red.