Awww, you guys! I've had this planned since BM! No one remembers it because no one actually talks to me about my own storyline (which makes me feel left out, but it's okay because everyone else needs more help), so I'm just disappointed no one ever really remembers what I have planned and then goes and comes up against something I had set for likes....decades (well no, not really -but it has been at least a year or two since Blastoise was my main point).
I also told you about it, when you first suggested the whole starter thing, and then you were like "Sonia's not likely to keep Charmander and will probably give it to Mal, and he'll end up with all three," etc. etc. And I also discussed this with Kenitoh...who sort of remembers my whole Blastoise point...and agreed to have Squirtle but keep it from becoming Blastoise for being the pokemon on the more speed side of his power group.
There was a whole plot based around Blastoise, which Mal doesn't even get until Celadon or Saffron City. As for battling, since Blastoise is fully trained, therefore Mal will definitely not be able to control it at all. But it is Leaf's and he wants to get close to her, hence why he's willing to try (another point I made back then, back when Mal had been "Raphael," and the whole Leaf plot was with him). Mal's also not really a battler or focusing on it, he just battles the gyms just because he's with the others. His interest lies more in inventing, etc. (hence why all his pokemon party seems to not be evolved and won't be)