Nidorino is larger than its pre-evolution. Its forehead horn is larger, as well as its ears and the spines on its back. It has grown large teeth.
It looks like you have to add tabs for the stings on it’s back yourself. I suggest making these tabs as small as possible, so that you don’t see too much of these tabs. You could also print out the spikes twice, and glue them together so you will have textures on both sides. It’s all up to you!
By POdragon, info from Bulbapedia