Sorry snake lovers, Brock's signature Pokemon can't get much more credit than this. It's design is really simple and boring, just a bunch of rocks slapped together to form a snake, whoopie. I don't really recall any character development in any of Brock's Pokemon, sans Vulpix, so I can't even give it much credit for anime awesomeness (only real memorable time was it losing to an attack it's immune to, lol anime logic). In the anime, he even evolves off screen (which I guess implies his siblings traded it away while he was gone, little bastards).
In fact if anything Onix deserves less credit for being Brock's because in HG/SS he's among the only gym leaders rematch (well, lol Claire she makes even less sense, really...) that has an NFE in his team. In fact, game Brock only ever evolved Onix in Round 2 of Pokemon Stadium 2 As far as battle usefulness, he was only fully evolved for the one generation that was dominated by Parasect and psychic types, so of course it was going to be UU. I will admit that in Pokemon Yellow, Onix was a legitimate threat. IIRC, Mankey was really the only Pokemon that was available at the time that you could effectively use against it without some hardcore powerleveling or a ton of potions (I do recall beating it once with just Quick Attack Pikachu, but I think it was level 16 by then). Even in R/B if you choose Charmander it's special defense was so low that Ember did well enough against it.
It also annoyed me that Bruno literally always had at least one Onix in his team when even in R/B he neglected Poliwrath and Primeape and had even more available options in future generations (well except Stadium 2 where his teams just threw his theme out the window anyway. Seriously, Granbull, Blastoise, Clefable, Muk, wtf). In fact the only time he had a pure fighting team was in the HG/SS rematch (The Hitmon Trio, Lucario, Hariyama, Machamp). It's little details, but it bugs me when gym leaders/E4 advertise themselves as a certain type and use others when there are available options (Except Dragons since Gyarazard gets screwed on typing anyway). Anyway, it seems that Onix has gotten away from me. Mediocre Pokemon, needed an evolution badly in Gen 2, got it and still kind of sucks, but more on that later.
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