>>12028849Charmander is a beast. During the main game, Smokescreen makes bosses laughable, and moves like Ember and Brick Break are fairly powerful. After evolving to Charizard, it can learn Heat Wave which affects the entire room. IQ wise, it is Type C which means it learns things like Type Advantage Master (Crit rate+ on SE moves) Aggressor (Attack up, Defense down) and Erratic Player (SE moves hit for a lot more, NVE moves hit for a lot less) so it will deal and take a lot of damage. Especially from Super Effective moves.
Eevee is a terrible partner but a decent leader as Run Away can really screw you over. Eevee also has almost no moves; Bite, Shadow Ball, Dig, Iron Tail, and a plethora of Normal and Status moves. However Adaptability can make up for the limited movepool, as all of Eevee's many Normal attacks will be doing a lot more damage. Post-game, the best Eeveelutions are probably Jolteon, Glaceon, Vaporeon and Leafeon in that order. The first three can all learn room clearing moves (Discharge and Blizzard x2) while Leafeon has a lot of type covering moves. Eevee's IQ skills include Type Advantage Master (which works best on Leafeon, although Vapor, Jolt and Glaceon can also use it well) and Multitalent (ALL moves have a permanent +5 PP, very good for those normally 7-12 PP room clearers)
Shinx's best use comes at level 41. It can link Charge -> Discharge for 3x damage against the entire room. Other than that, it can learn Bite, Crunch, Quick Attack, Spark, Thunder Fang... and not much else. It's IQ Group C like Charmander, but can't use it as well as Charmander can.
Totodile and Munchlax are IQ Group E which gives them things like Cheerleader (allies attack go up), Deep Breather (Each new floor, 1 move not at max PP will recover a single PP) and Quick Healer (Natural HP recovery doubled). Totodile has among the highest starting Attack and Sp.Attack out of all the potential starters and learns some decent moves such as Water Gun, Ice Fang and Bite.