How can a Gym Leader become a Champion?

Question

Let's say a Gym Leader wanted to be a Champion - would he/she have to collect all 8 gym badges from that region? If so, for his/her gym badge, would he/she just take without a battle or battle one of their siblings?
Please help me! Thank you so much! :)

Comments

I'm pretty sure they would just do it how trainers do it. If not then they'd probably hav a different challenge to go through.

Answer 1

The Gym leader will not have to go through the usual norms as a Pokemon trainer, they can go directly to the league and challenge whenever they want.
My proof here is going to be Volkner from DPP:
>All right, I've decided! If I find you to be weak, I'm going to challenge the Pokémon League.

But he's also said to be the top Gym leader in all of Sinnoh, so it's a reasonable theory that he has all the authority to go directly to the league, but in Pokemon origins, it is shown that Brock deliberately uses his weaker Pokemon against Red, as per his gym badges to match his strength, which means it's highly likely that if they had battled later, he would've used something else, meaning that all Gym leaders have about equal strength, atleast in levels.

Also Gym leaders are directly promoted by the league, which means they are acknowledged strong trainers, and have all the right to challenge the league, as long as it does not disturb their position as a Gym leader

Source: Some bit of knowledge in the game, and this about Volkner.
Hope I helped!

Answer 2

>It is the title held by the Trainer who last defeated the Elite Four and the previous Pokémon Champion.

That is the answer to your question for the games. They don't have to beat all the gyms, just the E4 and the champion.

While yes, you do have to beat the gym leaders first, the already existing gym leaders are probably picked by the league and can challenge it any time(this isn't official info, just how I think it can be).

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In the anime it's most likely the same, or the champion always stay the same and the people who beat them get a title or something to show that they did in fact beat the league(I don't really watch the anime though, so sorry if I got it wrong).

Source
Hope I helped. :]