Odd One Out

[Squirrel]

Zubat isn't one of those annoying first-route rodent things! (Most of which I adore :D)

Dialga, Azelf, or Mew?

 

[DyingWillFlareon]

Mew is from Gen I, the others are IV.

Rattata, Zigzagoon, Bidoof.
(The cutest of the first route rodents. :D)

 

[Precious~Dark]

Mew is from Gen I, the others are IV.

Rattata, Zigzagoon, Bidoof.
(The cutest of the first route rodents. :D)

I have to disagree

Bidoof has two egg groups (Water1 and field) Rattata & Zigzagoon only one (field)

Spheal, Seel & Oshawott

 

[Squirrel]

Oshawott is the only one I hate that doesn't become Ice-type!

Pikachu, Pachirisu & Emolga?

 

[Foxrally]

Emolga, as it doesn't start with a P and is a dual-type unlike the other two :)

Magneton, Dugtrio, Doduo.

 

[Pendraflare]

Doduo only has two heads.

Machamp, Hariyama, Mega Medicham.

 

[Lycanthropy]

Mega Medicham is the only Mega Pokémon.

Gastrodon, Tyranitar, Conkeldurr

 

[Squirrel]

Conkeldurr is the only non-pseudo-legendary there!

Seismitoad, Gothitelle, Klang?

 

[Foxrally]

Klang, as it is the only NFE Pokemon.

Rotom, Castform, Drilbur.

 

[Squirrel]

Drilbur is the only Pokémon that doesn't change forms!

Squirtle, Chikorita, Torchic?

 

[Meadow]

Torchic is the only one who evolves into a dual-type Pokémon!

Elekid, Magby, Smoochum

 

[Lycanthropy]

Smoochum is the only one which didn't get a third evolution in Gen IV.

Gengar, Alakazam, Golem

 

[Squirrel]

Alakazam is the only mono-type of the three!

Staryu, Starapter, Bellossom? No it isn't the names

 

[Precious~Dark]

Staryu is a genderless pokemon. Bellossom & Starapter have both a 50% male/50% female gender ratio.

Metapod, Silcoon & Spewpa.

 

[Squirrel]

Spewpa is the only one with an evolution that has different colours!

Flareon, Jolteon, Vaporeon?

 

[DyingWillFlareon]

Flareon was the only one to have a 'pokegod evolution' in Gen I lore!

Gengar, Mismagius, Drifblim.

 

[Lycanthropy]

Drifblim is the only species of which Fantina's one doesn't have the move Confuse Ray in Diamond and Pearl.

Dusknoir, Rotom, Spiritomb

 

[Squirrel]

Dusknoir is the only one to have evolved!

Pachirisu, Minun, Emolga?

 

[Pendraflare]

Emolga is Flying-type.

Weezing, Muk, Swalot.

 

[Lycanthropy]

Weezing is the only one not learning Sludge Bomb through levelling in Gen III.

Donphan, Marowak, Diggersby

Weezing is the only one not learning Sludge Bomb through levelling in Gen III.

Donphan, Marowak, Diggersby