The only true one that really comes to mind is Gyarados with the ever-crippling Water/Flying type. Naturally, Gyarados should have been the first Water/Dragon type of the Pokemon games, because it has more Dragon qualities than flying Pokemon qualities, and it doesn't even learn any flying type moves; on the other hand, it learns a few Dragon moves, including Dragon Dance, and most likely in Platinum, Outrage. (anyone with Platinum can confirm?)
Empoleon is another that shouldn't really be a type that it is; Steel doesn't really fit a penguin, but then again, does Electric to a mouse? XD But I personally think that Ice would have been more fitting for Empoleon; as Froslass mentioned.
I think Luxray should have been part-Dark, since it kind of looks like a Dark-type, in my opinion. It would also make it the kind of Electric counterpert to Houndoom, which is Dark/Fire.
I think either Poison or Dark should have given way for Bug on Drapion. The Dark typing just kind of seems a bit random, if you ask me.
It's nice to see someone here paying attention to me. Gyarados probably isn't Water/Dragon because the only weakness of this type combo is Dragon, and there weren't any varying in damage Dragon-type moves in R/B/Y. The same would be true abour Dratini and Dragonair not beeing Dragon/Water. Still, it doesn't make sense that Gyarados, Dratini and Dragonair, that are based on sea serpents and/or the Chinese dragon, wouldn't be Water/Dragon or Dragon/Water.
Luxray does look like a Dark-type, but so do maybe half of the Ghosts in the game...
I don't think Drapion should be part Dark, and I also think Ariados shouldv'e been Posion/Dark as well. They aren't Bugs!
I think Glalie's type should be Ice/Dark. Actually, when I first battle Glacia in e4 in Emerald, I wa sso sure that Glalie was part-Dark. I mean come one, don't you think Glalie looks sinister? And yes, Froslass would make a great counter-part ith the half-dark Glalie.
Gyarados. I mean, -FLYING!? Oh come on. I think it should be pure water as it is considered as a counter-part of Milotic.
Luxray, Electric/Dark would make a good combo. And I don't kno why,but i like Girafarig as a Normal/Psychic.
But seriously, I think Staraptor should be a Flying/Fighting. I learns Close Combat which makes it very good as a fighting, and a Roserade as a Grass/Fighting.
Glalie actually looks Dark-like and learns alot of Dark-type moves, but the pokedex also mentiones it having an armor of Rock. But, yet, I do agree Ice/Dark would be better than Ice/Rock, so yes...
I also think Seviper shouldv'e been Posion/Dragon. A viper snake, a
very cold-sensitive animal, without an Ice weakness? How is that possible?
Dewgong should just be Water-Type, being a dual type doesn't really fit it and I don't quite understand how its related to Ice in any way.
Dewgong is called the "sea lion pokemon". Sea lions are present in tropical seas, but not polar ones. But as most of us already know, pokedex entries aren't very reliable (Umbreon spraying posion? It can barely learn Toxic!), so it's probably based on a seal rather than a sea lion (Seel...the only pokemon name more obvious than this is Meowth), a common animal (but not exclusive) in polar seas. Mamoswine holds boar-like features, how boars are related to Ice. Anyway, designers of computer/video games probably don't know much about the animal world, roller coaster tycoon 2's "wacky world" expantion included inuits, iglues and polar bears in Antarctic theming. But as Water/Ice is the most logical type for a seal, it
should be Water/Ice. And because it's both a Water-type and an Ice-type, I really really like it :D ...