Since the original adaptation aired in 1997, Ash's Pikachu has always been by his side on his almost thirty-year quest to become the greatest Pokémon master. With Ash leading the way, Pikachu has managed to defeat pretty strong opponents despite being a pre-evolution form of Raichu. Even normal Raichu pale in comparison to the power of Ash's Pikachu. So what made his Pikachu so special? Why was it so much more powerful than its peers? Three different theories may answer this shocking inquiry.
Ash's Pikachu Has Always Been Powerful
As seen in the first episode of the series, Ash's Pikachu used a thunderbolt powerful enough to defeat an entire army of Spearow. Although Spearow is weak against electric types, these Spearow were most likely at the same level as Ash's Pikachu was at the time. This would have made it impossible for Ash's Pikachu to have displayed such an outstanding amount of power, especially during its first encounter. Even Professor Oak mentioned there was a "problem" with Pikachu before he gave it to Ash but doesn't explain what he means. This ambiguous problem might actually have referred to an excess of electrical generation, which isn't necessarily a bad thing, to begin with.
Ash Powered Pikachu Up
In the second episode of the original anime, Pikachu was receiving treatment at a Pokémon center after the battle with the Spearow in episode 1. In order to regain its strength, a horde of Pikachu charged it with electricity. Once Ash's Pikachu was back in fighting shape, it requested even more power, and that wish was granted. Before defeating Team Rocket, Pikachu harnessed even more power through Misty's pedal-powered bike light. This may have had a permanent effect on the beloved mascot, and even Team Rocket noted that Ash's Pikachu is rare as they were defeated. Pikachu's electrical prowess is again demonstrated in Episode 5 when it is seen overloading a hydroelectric powerplant in preparation for a rematch with Rock-type gym leader, Brock.
Another theory floating around suggests Ash's Pikachu was powerful because Ash himself had a powerful personality. It is said that Pokémon who are close with their trainers adapt the same personality. Since Ash is such a go-getter and extremely determined for ultimate greatness, naturally his Pikachu would have the same determination.
Pikachu is Maxed Out
Pikachu and Ash have been by each other's side for a long time. As they both are determined to become the greatest that the world has ever seen, they surely would be working on maxing out stats like the IVs and EVs in the game. There is no question that Ash's Pikachu would be maxed out at level 100 if it was depicted in the video games, but it is unconfirmed if the anime follows these same rules. There have been mentions of gaining levels in the anime, but there is no confirmation of whether or not there is a level cap similar to the games themselves.
There is no question that Ash's Pikachu is a good fit for Ash. Being the protagonist of the series, it is important that he has a suitable partner Pokémon to fulfill his ultimate goal of being a Pokémon master. Whether it be by default, or through powering up, or through the cumulative years of training together, Ash's Pikachu is definitely no ordinary Pikachu.