I know how hard it is to come up with nicknames for pokemon, here are some of the ones I am proud of.

Noctowl- Nocturne, Saren, Soren
Dragon like pokemon- Draken, Toruk (see Avatar), Scourge, Skywarp, Sauron, Quetzal, Dragoon
Infernape- Vulcan
Fire Type- Coal, Hephaestus,Infernus
Grass type- Verde,Veggie
Tropius- Tropicana
Gyarados- Leviathan, Typhoon
Water Type- Splash, Atalntis, Atlantica, Neptune, Posiedon, Tsunami, Seaspray, Triton
Starmie- Starwii
Castform- Forecast/4cast
Porygon Z- Skynet, CYBERDYNE, Cybertron, Cybercop (Cyberpolice doesn't fit)
Togekiss- Archangel, Normandy
Skarmory- Starscream
Flying type bird- Talon,T-Hawk
Smeargle- Artisan, DaVinchi
Aggron- Gojulas
Large pokemon- Titan
Eletric type- Raiden/Rayden, Jolt, Electro, Blitz, Tesla
Medicham- Karma
Machamp- Spartan
Espeon- Saix
Alakazam- Apocolypse, Magik, Yen Sid, Hocus, Pocus
Crobat- Vamp
Ghost Type- Shroud, Grim, Fantasma, Spectre
Raticate- Splinter
Girafarig- Domino
Crocodile pokemon- Sobek/ Sebek, Chomp, Krawk
Clefairy- Faerie, Pixie
Onix- Tektonix (stole from Fire Red NPC)
Tauros- Taurus, Dozer, Rampage
Ampharos- Ozymandias
Tough looking pokemon- Ironhide, Devastator, Colossus, Juggernaut
Ice type- Frigid, Frost, Everest, Hailstorm
Dialga- Eternity, Kronos
Palkia- Infinity
Giratina- Oblivion, Renegade
Registeel- Megatron
Gallade- Psyblade, Excallibur
Glaceon- Bubastis, Frozone
Claydol- Totem
Zangoose- Axel

Just a few of the ones I like. I usually grab names from pop culture or myth.

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