>>32181415I will poost
>>32181427Arceus, Keldeo, Meloetta, and Genesect are technically the rarest ones because all the others can be obtained with the right game, item, or bonus material.
Mew can be obtained from both Pokemon Ranch (Haley's Mew) at any time, and through player made code execution in RBY on the eshop (Requires precision but no external tools or outright injection).
Celebi can be obtained 48 times from each Japanese Colosseum bonus disc. I would put it with the top in terms of rarity due to the difficulty in obtaining a disc though.
Jirachi can be obtained from both the english colosseum bonus disc and Pokemon Channel.
Deoxys isn't mythical anymore.
Manaphy can be obtained from Pokemon Ranger (only once per cart though).
Phione, well you breed Manaphy but if that didn't exist then Ranch gives you one too.
Darkrai can be easily caught without the event ticket through the surf glitch.
Shaymin, same as Darkrai but will not be "fateful" and cannot transform to Sky Forme.
Arceus can never be obtained without an event, as many Hall of Origin Arceus simply can't be transferred, although some outliers exist and can be.
Victini is very easy to obtain if you either use glitches or just get traded a Pokemon holding the ticket.
All successive event legends barring Magearna are impossible to obtain without an event.