It may surprise some Pokemon fans that Charmander is actually the weakest of the first generation of starter Pokemon, although dedicated fans of Squirtle and Bulbasaur will probably agree with that statement. It probably isn’t nearly as surprising that Charmeleon is not as good as Wartortle and Ivysaur, Pokemon that can actually succeed outside of a particular niche. All that being said, Charmeleon is a better Pokemon than Charmander, albeit nowhere as cute, as he picks up significant boosts in Special Attack and Speed that serve him well in a niche, but powerful role, as a Sunny Day sweeper.
Like Charmander, Charmeleon gains Solar Power. Unlike Charmander, he’s already fast enough that he can have a Modest special-attack boosting nature rather than a Speed boosting nature. This is important because it means he hits even harder and even quicker especially with full Effort Value investments in Special Attack and Speed, plus a Choice Scarf. He can even pack Toxic and Ancient Power, moves that you wouldn’t see on a Charmander who has to go all in on Fire-type attacks. Charmeleon’s Fire Blast also hits hard without Sun up, meaning he’s not quite the one-trick pony that his first stage happens to be.
The problem is that despite these positive attributes, you’re not going to see Charmeleon compete at a high level like Eviolite-packing Ivysaur and Wartortle can. He becomes quickly outclassed outside of the niche NFE (Not Fully Evolved) metagame, which while fun, isn’t really much more than a niche for those who want to explore the possibilities of middle evolutions like Charmeleon.
Heck, I’m well-aware that in the early days of Pokemon, many players would keep Charmander around until level 38 to learn Flamethrower, then use Rare Candies to evolve him to Charmeleon but also immediately into Charizard. While this sounds like a difficult strategy, consider that Charmeleon doesn’t learn Flamethrower until 42, and level 46 for Charizard. While Flamethrower isn’t common on Charizard in competitive play, it is on in-game playthroughs, thanks to being far more accurate than Fire Blast. Having Flamethrower on a level 38 Charizard is a huge competitive advantage in the adventure, believe me.
So, is Charmeleon a good Pokemon? It’s fair to say that Charmeleon is good in much the same way that Charmander is good, by virtue of evolving into Charizard, who most certainly is a good not great Pokemon on his own. Like Charmander, Charmeleon needs the benefit of Sun setters to be really any good, although his Fire Blast with Choice Scarf is going to hit hard and first much of the time. Unfortunately, Charmeleon is easily one of the more forgettable middle evolutions of any starter Pokemon line, and perhaps, that’s okay considering what he inevitably can become.