Rival Pokemon

[ShinyBlackWhite]

Dusknoir and Chandelure. Chandelure feeds off of souls, but would be unable to if Dusknoir sent the souls to another world.

Spinarak line and Joltik line, compete for best spider pokemon.

Venomoth and Butterfree.

Bidoof and Rattata, most annoying first encounters

Pachirisu and Emolga, best squirrel

Cacturne and Maractus

Legendary beasts and legendary birds

Magnemite and Voltorb.

I can keep on going with this forum all night.

[Jdrawer]

Pidgey line vs Spearow line, but that's canonical, isn't it?
I feel Arbok is rivals with eithe Pikachu or Raticate.
Marowak seems like it'd be rivals with- gosh, I can't think tonight- maybe Machoke?
Oh, and thanks for having mine be your favorite! ^-^

[TheGreatGigInTheSky]

Reshiram and Zekrom. Truth and Ideals. Does nobody remember the legend from Black and White when Reshiram and Zekrom split from the original dragon (presumably Kyurem) and battled, in the process nearly destroying Unova? It is only natural that there is a rivalry. Also, only one is able to fuse with Kyurem at a time.

[gustavo 14]

Reshiram and Zekrom. Truth and Ideals. Does nobody remember the legend from Black and White when Reshiram and Zekrom split from the original dragon (presumably Kyurem) and battled, in the process nearly destroying Unova? It is only natural that there is a rivalry. Also, only one is able to fuse with Kyurem at a time.

Well, of course that one is known, but this thread, as stated by the OP, is geared more towards the less obvious rivalries.

So far, of ones that haven't been thought of, I'd say Gigalith and Golem. Gigalith is very similar to Golem, but Gigalith is composed of compressed rock with a solar core with power that it can use to blow away mountains, and Golem tends to like hanging out in mountains, rolling around them and whatnot. These two would clearly tend to have issues getting along.

[Serebii!]

Mew and Mewtwo

[Ryan7437]

I know this is crazy but Oshawott VS. Piplp. They were rivals in the anime and seem to fight for being the cutest.

[Auaria~]

All of the tiny Legendaries could be rivals.... They're all extremely popular, especially Mew and Celebi, and they all have the same base stat total of 600...

[CyberBlastoise]

Well, I have a couple.

Lucario vs. Scrafty. (since Zoroark was already taken). One of them is a noble fighter who keeps his heart pure, or something like that, not to mention the ability Justified. The other is a dirty fighter that has little semblance of honor it seems. Both are weak to Fighting.

Drowzee vs. Munna - Both eat dreams, but one gets sick while eating bad dreams and the other will go to people with bad dreams to eat them away.

Alakazam vs. Gengar - This one is more focused on typing than anything else. Well, that and they're both evolved through trading rather than training. =P

[Trainer Frankie]

Mincinno and Trubbish
One's meticulously clean, the other's garbage.
Substitute any of the following for Trubbish:
Koffing, Grimer, Wooper, Stunfisk, Barboach.

There's also, if I'm remembering correctly, the fact that in White 2''s Route 4 there are wild mincinno while in Black 2 it's replaced with trubbish.

[Masterofknees]

Electabuzz and Scyther after the animé episode 42 'Showdown at Dark City' in which the two rival gyms fight each other (and get covered in ketchup)

I do think that Scyther's rival Pokémon has always been meant as Pinsir, seeign that you get them in their seperate versions, same place, both bug, etc. Where as Electabuzz's rival is obviously Magmar.

[Hejiru]

Well, Zangoose and Seviper obviously.
Durant and Heatmor are obviously meant to be enemies.
Same goes for Shelmet and Karrablast.
Meowth and Murkrow steal from each other.
The two forms of Basculin are said to be enemies.
And several legendaries: Groudon & Kyogre, Cresselia & Darkrai, Reshiram & Zekrom.
(As I recall, Dialga and Palkia were only enemies in the anime.)

Those are the only confirmed ones I can think of at the moment.

And then there's some that are speculation. Lucario and Zoroark for example. To begin with, there's the fact that Fighting and Dark are conceptual opposites. (Fighting with honor vs using dirty tricks to win.) Plus they played a very similar role in their generations. They were both "Mascot Pokemon"; among the first revealed for that generation, used to promote that generation pre-release, non-legendaries who got their own movies, and both come from two-stage lines. But what's most interesting is that they have opposite powers: Zoroark creates illusions to deceive people, while Lucario has the power to see the truth. Zoroark creates illusions and Lucario sees through them.

Pinsir and Heracross might be one, due to the this common Japanese trope. Heracross is part Fighting-type and Pinsir learns many Fighting-type moves by level up.

I've always felt that Camerupt and Waillord were related. Not enemies, but just counterparts. They're both 2-stage lines from 3rd Gen and their types personify Team Aqua and Team Magma.

There's a lot of other Pokemon that are counterparts, but not enemies, too many to list. Arcanine and Ninetales, Solrock and Lunatone, etc.

[ShinyBlackWhite]

Grimer and Voltorb both would seem to be natural enemies because they can both live in power plants.

[AyameTori]

Mewtwo vs Arceus

I don't see that??!!?!!?

[Rebel562]

Entei's roar makes volcanoes erupt. Camerupt is biologically a volcano. Something could be going on there.

Growlithe and Lillipup are both "Puppy" Pokemon.

I've always felt a competition between Mighteyana and Linoone. Both two-stage Pokemon found in Hoenn's starter route, both weak to Fighting.

Glalie and Cryogonal. Giant ice faces. 'Nuff said.

[Jdrawer]

Camerupt and Magcargo

[Crimson101]

Pikachu vs Pachirisu vs Emolga!

[SlenderMan0]

Sawk/Throh vs Hitmonlee/chan
Both are fighting types worried about their strength.

[!jirachi!]

mewtwo vs genesect they were both created by scientists
though mewtwo 1 hit KO's genesect

[Greatemboar]

Heracross and Pinsir look at them two beetles one with a single horn the other with two

[Personosrep]

Lopunny and Bibarel
i'll let u figure it out