I assume you mean by this Rattata, Sentret, Zigzagoon, Bidoof and Patrat? Hmm… Well, Patrat has those crazy eyes, and I’m pretty sure it’s some kind of demon-thing. It scares me. I think Rattata is just a really big purple rat; like, I’m pretty sure it doesn’t do anything that a normal rat doesn’t. Bidoof is Bidoof. Zigzagoon has the zigzag thing, which I guess is kind of interesting. I suppose I quite like Sentret. It’s a meerkat, only it’s not, because it’s also a bit like a whole bunch of animals. It’s not just an animal that’s been pasted into the game with minimal thought or development. Also there is that episode of the anime where a Sentret hijacks Team Rocket’s giant Arbok-shaped destructo-tank, possibly the most ludicrous device they have ever deployed (which is saying something), and goes on a rampage. That was, on reflection, pretty awesome.