Legendary catching

[Kreyexx]

Okay guys, this might sound stupid at first because of the title but let's consider it like this.
After 6 years of playing some people have almost reached the title of "catching'em all", even though there are always added new spawns they're still close enough. But have you ever thought how do they feel after seeing that they miss the legendary pokes in catch? That they simply can't catch it all? Well here are 2 suggestions I've think off and you decide for me if it's good or not.

-After catching all pokemons from kanto region the player receives balls such as "Thunder Ball/Flame ball/Freeze ball" (legendary birds) also there's "Serenity/Calamity ball" (Mew/Mewtwo) but you will only get one of these balls which will count almost as a master ball. Rares of legendary pokes are rare that's why I said only 1 ball. If the player has the most damage he will be allowed to throw one of those balls on it and be able to catch it.

-Some of you may think it would be abusable because people would have legendary pokes at them, well that's why I said I have 2 suggestions:
1)After they catch it, make it unable to use, just get it as a new catch and then sell it to NPC for 10k(Could be adjusted)
2)Make it possible to use but not having too high stats, just like other good pokes.

Trust me, they would be ultra rare because how many people have caught all 151 original kanto pokes? Let's not forget Johto/Hoenn too. Also legendary rares are rare themselves, but even getting highest damage percentage on one of them is even harder.
This idea would motivate people to catch more and also be nice for those who actually want to catch'em all.

 

[Sheeper]

No legenadary catching ever. They should remain as bosses, players who caught all pokemon from first 3 generations might get some epic reward, but not this. I'd rather make some pokemons Ultra rare to get, for example some hard quest for high level (requiring for example 320 catches) to unlock access to toxicroak, bronzong, luxray etc.

Generally, disagree with any kind of way to obtain legendaries

 

[Kreyexx]

No legenadary catching ever. They should remain as bosses, players who caught all pokemon from first 3 generations might get some epic reward, but not this. I'd rather make some pokemons Ultra rare to get, for example some hard quest for high level (requiring for example 320 catches) to unlock access to toxicroak, bronzong, luxray etc.

Generally, disagree with any kind of way to obtain legendaries

That's why I made 2 options, and one of them is to make them unable to use, but just for catch, what's the point in famous saying "catch'em all" if you still can't do it, and I think this might be a nice and hard way which takes tons of effort do it.

PS. Forgot to mention that you can only throw one of these balls you receive on the legendaries, and not normal balls.