10 Most Ridiculous Pokémon Ever
3. Unown
Pokédex - 201 (Generation II)
Many Pokémon become somewhat redundant and/or surpassed by new creatures in subsequent games. Legendaries for one, though they remain notable as a result of their rarity. None have become more redundant than a side-quest based Pokémon that was useless for anything outside of said quest to begin with though: Unown.
The unoriginally named beast (the word 'unknown' with two fewer letters must've taken a long time to come up with) was the focus of Gold and Silver's Ruins Of Alph, which involved solving sliding puzzles to make different Unown varieties appear through its various caves.
There were twenty eight in total, one based on each letter of the alphabet and two additionally based on an exclamation mark and a question mark. Though there was no benefit to catching them all (or even catching one, given that each only possessed a single move, Hidden Power, and couldn't learn any more from levelling or from TMs), it was an irritating requirement for perfectionists wanting to catch every single Pokémon available to them.