>>47100368>mewRumored to be the ancestor of all pokemon because it can learn every TM, though this is put into question by the existence of other ancient pokemon like Arceus
>CelebiTime travel, which Dialga also does
>JirachiGrants wishes, which Hoopa also kinda does
>DeoxysConfirmed alien
>Manaphy/PhioneLiterally just rare mons
>DarkraiMuh nightmares
>ShayminPurifies air and grows flowers
>ArceusSupposedly created the universe, probably can't be confirmed due to the timescale involved, but very powerful guy in general
>VictiniUnlimited energy
>KeldeoSmall rare horse
>MeloettaIt's singing and dancing makes people happy, which most pokemon can probably do
>GenesectLiterally just a cyborg
>DiancieMutant Carbink
>HoopaMuh warp rings
>Muh steam>MagearnaLiterally just an artificial pokemon like Claydol or Golurk
>MarshadowRare ghost
>ZeraoraRare cat
>Meltan / MelmetalThey eat metal I guess
>ZarudeRare monkey
Also, Dratini used to be considered a mythical pokemon until it started being discovered more often. So yeah, the majority of mythicals only really have rarity going on.