Odd One Out

[Starry Windy]

Cresselia has no teammates :c

Arcanine, Ninetales, Lampent.

 

[blue]

Lampent is the only one with a three stage evolution!

Staraptor, Noctowl, Sigilyph

 

[Lycanthropy]

Staraptor is the only one with a higher attack than special attack.

Misdreavus, Unown, Murkrow

 

[Sirfetch’d]

Unown doesn't evolve and doesn't start with M!

Sylveon, Altaria, Klefki?

 

[Starry Windy]

Altaria is not a Fairy type. Except when it Mega Evolves.

Caterpie, Weedle, Wurmple.

 

[Sirfetch’d]

Caterpie doesn't have Poison Sting!

Slugma, Grimer, Trubbish?

 

[JJ Styles]

Slugma isn't a poison type.

Pidgeot
Zapdos
Feraligatr

 

[Sopheria]

Feraligatr is the only non-flying type.

Doduo
Espeon
Kirlia

 

[Starry Windy]

Doduo is not Psychic types, obviously.

Whiscash, Seismitoad, Lanturn.

 

[Percy]

Lanturn is the only one that is not a Ground type.

Raichu, Lairon, Igglybuff.

 

[Pendraflare]

Lairon is the one who isn't among "pixie" groups (Pikachu, Jigglypuff, etc).

Empoleon, Tentacruel, Ludicolo.

 

[Starry Windy]

Tentacruel is the only one that is part of two-stage evolution.

Swellow, Swalot, Swanna.

 

[Nidorina of Time Lord]

Swalot is the only one that isn't a bird!

Magby, Igglybuff and Pichu

 

[blue]

Magby is the only one not to evolve by high friendship.

Stoutland, Houndoom, Luxray.

 

[JJ Styles]

Houndoom is the only special attacker in the group.

Pidgeot
Venomoth
Charmeleon

Note: You have to be a little more creative in knowing the group behind it. Obvious answers such as typing and whatnot aren't counted. It refers to a phenomenon.

 

[Guardian]

Ash never owned a Venomoth :P

Rattata, Zigzagoon, Patrat.

 

[JJ Styles]

Only Zigzagoon can learn Extreme Speed.

Rhyperior
PorygonZ
Conkeldurr

Spoiler:

Ash never owned a Venomoth

so close but not quite but good try though :P

Spoiler:

Its a twitch plays pokemon thing

 

[Nidorina of Time Lord]

Conkeldurr is the only one that doesn't need an item to evolve when traded.

Poochyena, Zigzagoon and Ralts

 

[Sirfetch’d]

Ralt's is dual typed!

Raticate, Golbat, Dugtrio?

 

[JJ Styles]

Golbat is not a fully evolved pokemon among the group.

Slurpuff, Vanilluxe, Miltank?