This is Goma, and obviously he's had a bit of a bad day. He's healed up okay somehow and got a cool fashion accessory out of it, his skull has calcified around it and luckily it's not just rattling around poking him in the grey matter

It did however hit him in the pituitary gland, so his growth is a bit stunted

The hollow horn base sometimes makes a low whistling noise if the wind hits his face at a certain angle during running or blustery days