[Creepy, that's for sure. Armin has heard things about this guy, enough to leave him slightly wary. He won't make up his mind until he's had some proof, but still, no sense cannonballing himself into potential danger either. That's Eren's schtick.]
R-right. It'll lose the golden colour when it reaches its final evolution and will turn black instead.
Video;
R-right. It'll lose the golden colour when it reaches its final evolution and will turn black instead.