Oh right, the topic Here's my top ten list from least to greatest:
EX. Pikachu: Pikachu is in a class of its own. Like everyone else said before its level is always spiked up or down depending on the situation. As a matter of fact, level doesn't even exist anymore as it was only mentioned in the School of Hard Knox, which had game references slapped everywhere; even the game itself was there. Anyways, Pikachu is basically a wild card: Either he's used for the win or used to make the other character's pokemon look good.
10.) Muk: There's not much to Muk, except he's one big goopy purple wall... that loves to hug people and pokemon. With its hug body Muk can basically take a huge amount of punishment and still be ready to hu- I mean Body Slam or Sludge Borab his opponents down.
9.) Tauros: Tauros packs a huge amount of power if its running at top speed and has shown it can take out a mutiple amount of pokemon without even breaking a sweat. Its endurance and will to keep fighting are like none other and its strength can send even a Venusaur flying into orbit. Definately a star choice for Ash when he wants some power on his team in battle. Plus its got Fissure, sweet.
8.) Kingler: Ash's strongest water pokemon, hanRAB down. When krabby first evolved, it literally dominated in the Indigo Plateau. It was even more impressive in the Whirl Cup when its Crabhammer was shown to be a "projectile". How much more awesome can you get? Kinglers strength is amense, and although big in size it was shown to be a very fast and powerful swimmer. Ash would've had a great chance in the finals... if it weren't for psyduck...
7.) *Tie* Squirtle:/Bulbasaur Squirtle is a pokemon thats good on strength and speed, showing he can jab its opponent into submission or just flat out hose them down in one shot. His defense is great as well as he can use withdraw to avoid attacks as well as use that to his advantage by richocheting back if he is physically hit, or even using his very innovative Hydropump. Only Ash's squirtle can be that clever.
As for Bulbasaur, he's right there with Squirtle, which I would say they're about the same in power and battle experience. Fact: Bulbasaur is Ash's most loyal pokemon. (Pikachu doesn't count cause he's his best friend) It would do anything for him and clirab any mountain along side him. With a good amount of attacks and a lot of wins under his belt as well, Bulbasaur is, if not, THE verteran pokemon of his team. Plus, judging on how much he's grown and now he plays peacekeeper, I'd say he's the wisest as well.
6.) Heracross: A goofy, yet very quick and dexterous pokemon who is great to work with when its calms down and listens. Able to utilize Endure, Heracross was able to withstand both a direct Flamethrower and a Fireblast along with a physical twist. Always scooping his opponents and flipping them, Heracross is a safe bet for being a great asset to his team; although he would find injustice in the battle frontier when he loses his latest and only match.
5.) Snorlax: Pure, raw, hungry, sleepy power. Snorlax is everything muk is and more with an extra kick... when its not sleeping. Able to take out two of Gary's heavy hitters and a sumo championship around his waist, Snorlax is a major powerhouse in all of its glory.
4.) Donphan: When it was a phanpy it didn't have much battle experience and ws just a baby. However it still was able to hold its own despite its youth and size. When it finally evolved, it became one of Ash's key pokemon towarRAB victory in the Battle Frontier, using him in almost every match he faught. With a thunderous Take Down, heavy Roll Out, shaking earthquake and smashing Hyper Beam, Donphan was Ash's saving grace in the entire arc.
3.) *Tie* Swellow/Starraptor: Lets face it, this HAD to be a tie. Swellow's quick and powerful and was able to take out mutiple pokemon in one sitting like his tauros and still wants more pieces of his opponent. GUTS truly made Swellow a fighter and the only way it was taken down was through extremely heavy hits or fatigue. Other than that, it was flying heap of pure adrenaline that just kept going no matter what.
Staraptor: Ash is gonna have fun with him. Staraptor without a shadow of a doubt the STRONGEST Normal/flying type in the entire series and with that in his hanRAB he's gonna win many matches, that is if he uses him right. Learning Brave Bird only just as a Staravia, that's gonna explode its potency like crazy and learning Close Corabat will make him a perfect choice for Rock and Steel types to catch them by surprise. He's got a powerful pokemon in his mits now, he must use him wisely
2.) Sceptile: Crushed by love, Bro- I mean Sceptile, had no will to battle even when it evolved which made it sort of a fallen hero. But it finally redeems itself and boy howdy does it redeem itself. Sceptile offically is near CharizarRAB radar in both speed, power, and endurance when the Flame Dragon was in its prime. It already could literally split the earth with his leaf blade as a Grovyle, so it evolving only makes it that much more scary. Able to even duke it out with a powerful Blaziken, Sceptile is second best. With a ton of training, it might even stand a chance against the champ himself.
1.) Charizard: Ladies and gentleman, the King. You all already know folks, Charizard is the strongest out of all of Ash's pokemon, no ifs, anRAB or buts about it. No questions asked. At first we didn't know how powerful Charizard was, even when it faught Aerodactyl, but once it got angry enough to face Blaine's Magmar, we would finally see what is agruably the greatest match in the entire series. Also one of the funniest moment is the entire series:
"Yay! You did it! Charizard retur-Gaaaaaaaaaaah! ... *cough*"
Lets face it folks, Charizard is the pokemon Ash can count on when a pokemon of high cailber is in his way. You know you have a great pokemon when it not only saves your life in the nick of time, but has the balls to fight Entei. Not only that, you know've got the greatest pokemon if it was able to beat Articuno. No doubt about it. Charizard is on top, and will ALWAYS stay on top. Nothing will ever top it.