Odd One Out

[Fil]

A stone, not leveling up, is needed to obtain Arcanine through evolution.

Remoraid, Feebas, Huntail

 

[Emboar]

Huntail is evolved.

Torterra, Mankey, Zubat.

 

[Lycanthropy]

Zubat is the only one without eyes.

Karrablast, Sewaddle, Burmy

 

[Precious~Dark]

Karrablast. Burmy & Sewaddle both have Overcoat as hidden ability.

Carbink, Goomy & Cyndaquil

 

[Fil]

Carbink (#703) and Goomy (#704) are consecutive in the Pokedex, while Cyndaquil (#155) is quite far off.

Stantler, Sawsbuck, Rapidash

 

[DyingWillFlareon]

Stanler is the only one with an evo. (MEGA STANLER)

Sneasel, Dragonair, Kyogre.

 

[Lycanthropy]

Sneasel is unable to swim.

Makuhita, Bulbasaur, Helioptile

 

[DyingWillFlareon]

Makuhita has only one type. unless you're playing snakewood coughcough

Vulpix, Eevee, Growlithe.

 

[DyingWillFlareon]

Mudkip is the only one who's evos are immune to Electric.

Mankey, Aipom, Machop.

 

[Starry Windy]

Aipom is the one among them that isn't a Fighting-type Pokémon.

Sylveon, Leafeon, Lumineon.

 

[DyingWillFlareon]

Sylveon is the only one who got a new type in a new gen.

Cyndaquil, Croconaw, Meganium.

Sylveon is the only one who got a new type in a new gen.

Cyndaquil, Croconaw, Meganium.

 

[Precious~Dark]

Cyndaquil is the odd one because Meganium & Croconaw belong in the monster egg group together and Cyndaquil doesn't...

Seaking, Masquerain & Drifblim

 

[DyingWillFlareon]

Seaking has only one type.(doesn't it...?.... If I'm not remmebering right then because it's from Kanto.)

Butterfree, Beedrill, Heracross

 

[Precious~Dark]

Butterfree is the only one who doesn't have a mega-evolution (I hope butterfree gets one in the future...)

Swinub, Remoraid & Teddiursa

 

[DyingWillFlareon]

Swinub has 3 evos(unless Mega-Ursaring becomes a thing).

Rufflet, Spearow, Hoothoot.

 

[Precious~Dark]

Rufflet because they have a 100% male gender ratio. Spearow & Hoothoot 50%

Purugly, Persian & Delcatty

 

[Lycanthropy]

Slowking is the only one not learning Rest by levelling.

Misdreavus, Taillow, Ponyta

 

[Foxrally]

Misdreavus as she is the only fully evolved Pokemon of the three :D

Snover, Scyther and Heatmor.

 

[Starry Windy]

Heatmor because it is stronger against the other two, also because it has H as its first letter instead of S.

Blaziken, Infernape, Delphox.

 

[Lycanthropy]

Delphox isn't one of those fire-fight starters.

Zubat, Poochyena, Rattata