I love Pokémon and have been watching the anime/cartoon ever since I was a little child! Pokémon is still popular!
This is one of Ash's only fully evolved pseudo legendary Pokémon (Goodra was released and probably not coming back very often). He is a steel type with a lot of raw power. Unfortunately, we haven't see much of it in battle. Even though it had a few victories under its belt. It's level is probably still low. Ash needs to train it more (than Pikachu) and definitely not leave it behind or release it. Melmetal has a lot of potential to be discovered.
Melmetal Ready to Fight!
This is a surprise right?! Who still remembers that he has a Kingler? This water Pokemon is one of the few fully evolved water type in his collection. Because he either releases his most powerful water monster (spoiler alert) or they just don't evolve. He used Kingler in the first Pokémon league (Indigo) and this guy defeated three Pokémon by himself! Ash has yet to repeat this kind of power in any other league. It's too bad that we don't see Kingler very often :(
Kingler in Action!
This is a tough flying type Pokémon. When Ash tried to capture him, he put up an impressive fight against Pikachu. Flying types are supposed to be weak against electric attacks, but Swellow (then a Taillow) endured many attacks without filching. This Pokémon fought hard and won Ash several battles. In the Crossgate PokeRinger competition, it used its determination to win and evolve into Swellow. As a Swellow, it defeated Winona's shiny Swellow with Ash's help. In another gym battle against Tate and Liza, Swellow teamed up with Pikachu to seal the win.
Thunder Armor? Swellow and Pika!
This Pokémon is strong, agile, and reliable. Ash captured him in the Orange Islands and didn't really have to give him any special training. He usually stays at professor Oak's laboratory, eating and sleeping all day. But when Ash called him, he doesn't disappoint. He won at the Sumo Conference, defeated Clair's dragon Pokémon, played a key role in the Silver Conference, and defeated Greta's fighting Pokémon (he's weak against fighting types). Despite being very lazy, this Pokémon packs a serious punch!
Snorlax Is an Agile Swimmer!
He is Ash's most powerful bug type Pokémon. When he first appeared, he was so cute! Even Misty (hates bug type Pokémon) likes him. After he joined Ash's team, he defeated many powerful opponents for Ash. In the Silver Conference, Heracross defeated Gary's Magmar despite the type disadvantage. In Lily of the Valley Conference, it defeated Nando's Pokémon. Against Tobias however, it was a good battle fought by Heracross, but that Darkrai was just too strong. This adorable bug type needs more training and attention from Ash. He is very strong already but more potential is still there. Also, Heracross is able to mega evolve. So what are you waiting for Ash, call Heracross back in your party?
Heracross Loves Bulbasur's Nectar!
A fully evolved grass type Pokémon that packs a serious punch. He's also able to mega evolve. When Ash first caught him as a Treecko, he is already very determined to win all battles. When he evolved into his final form, his power grew even more. Sceptile's most important wins were against Spenser (Palace Maven) and Tobias. Most impressively, Sceptile scored a knock out against the legendary Pokémon, Darkrai.
Ash and Sceptile
Ash always gets powerful fire type Pokémon and it usually evolves into its final stage. Infernape was Paul's Pokémon. But Paul released him. Fortunately, Infernape was able to join Ash's team. Lucky for the both of them! Infernape met his rival Electivire in the semi-finals of the Lily of the Valley Conference. Not only did he beat Electrivire in the final show down, Infernape defeated three of Paul's Pokémon. Talk about power!
Infernape Blaze Activiated!
In place of mega evolving one of his old Pokémon, Greninja was able to synch with Ash without the mega stone and became Ash-Greninja. Greninja is one of Ash's few fully evolved water types (the other one being Kingler). Undoubtedly, Greninja was Ash's most powerful monster is XY. But Ash had to release him :(
One of the most recognized Pokémon of all time, just behind Pikachu I think. Because of his popularity, many Charizard Pokémon cards are very expensive and rare. Charizard joined Ash's team because his old trainer abandoned him. As a Charmandar, it was so cute and nice. But after evolving, it was no longer that cute and nice Pokémon that we know. Ash had to prove to Charizard that he is a worthy trainer to Charizard. It defeated many powerful foes such as Blaine's Magmar, Clair's Dragonair, and Gary's Scizor/Golem/Blastoise. It even defeated one of the legendary Pokémon, Nolan's Articuno in the battle factory. If Ash is able to mega evolve Charizard, he might be unstoppable. But, Ash hasn't called on Charizard for a while. Pokémon is starting to downplay Ash's Charizard. Because why didn't he mega evolve into Charizard X or Y? If he did, again, Charizard would dominate and steal the spotlight.
Why is Pikachu first? Sometimes, he is very powerful. But other times, he's easily defeated by another weak Pokémon. Let's talk about some of his notable battles.
Against legendary Pokémon? No problem!
Against mega evolved Pokémon? No problem!
But against a weak Pokémon? Maybe not!