First off, it's Eagun. Second, don't Type Like This, it makes it incredibly hard to read.
Why is that rubbish? Maybe he didn't overly-train is Pokemon.
Well he hardly trained it then. The guys like at least 80. If he got it when he was 10 and it was level 5, then that's 45 levels in 70 years. That's pathetic.
This post says it all, really.Well perhaps, just like with people and animals in real life, a long period of no training or excercise caused the Pokémon to gradually grow weaker, and consequently lose some of it's levels. If I remember right, Eagun mentions somewhere in the game that it had been awhile since he and his Pikachu last battled, so maybe it's lower level reflects this.
Anyways, there are a lot of things in Pokémon that make little to no sense, but it's a game. It's allowed to be that way C: