>>54154361>I forgot, what was missingno supposed to be again?It's a bunch of junk data that gets generated when you perform certain actions in a certain order. There's also actually multiple Missingno., and the slots they occupy are all that remains of several cut Pokemon from the old beta. Nothing is left of the missing 'mons at this point except their cry data, though the leaked beta has back sprites that match the IDs of the Missingno.s, plus Tajiri's biographical manga had an image with some front sprites that matched a few of the known back sprites, letting us guess what at least some of them would have looked like.
The first Missingno. slot on the list, previously occupied by a Pokemon shown in an early sketch as 'Omega', is known to be the slot that Mew was slipped into at the last second, so generating that specific Missingno. now summons Mew instead of a garbled glitch monster.
Just remember: Every time you spawn a Missingno., you're actually conjuring up the ghost of an erased beta Pokemon, only distinguishable by its cry.