Pokemon Competitive Singles sure does exist. Gyarados is a part of the Metagame. It evolves from Magikarp in a humorous turn of events.
How to Gyarados Shiny Farm is another question entirely. Gyarados has a low value Shiny since there is a set encounter with a Guaranteed shiny Gyarados in the Lake. It's a red Gyarados. So I would not advise Gyarados Shiny Farming in the first place as I believe this to be a fools errand.
JimCool knows stuff like this. You can put your trust in Jim Cool for factoids like that.
0:00 Intro
01:17 Gen 1
03:52 Gen 2
04:18 Gen 3
10:33 Gen 4
13:25 Gen 5
14:59 Gen 6
17:37 Gen 7
18:55 Gen 8
21:09 Gen 9
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