Badnik

Badniks are mass produced robots created by Dr. Eggman to serve as common enemies throughout the game. They ar epowered by little animals which Sonic can free by destroying the badniks. Badniks come in a wide variety of designs and models, suited for the various environments throughout the games.

Sonic the Hedgehog 1991

 * Ball Hog
 * Bat Brain
 * Bomb
 * Burrobot
 * Buzz Bomber
 * Caterkiller
 * Chopper
 * Crabmeat
 * Jaws
 * Moto Bug
 * Newtron
 * Orbinaut
 * Roller
 * Spikes

Sonic the Hedgehog 2

 * Aquis
 * Asteron
 * Balkiry
 * Buzzer
 * Chopper
 * Clucker
 * Coconuts
 * Crawl
 * Crawlton
 * Flasher
 * Gohla (Sol)
 * Grabber
 * Grounder
 * W:C:sonic:Masher Badnik
 * Nebula
 * Octus
 * Rexon
 * Shellcracker
 * Slicer
 * Spiker
 * Spiny
 * Turtloid
 * Whisp

Sonic CD

 * Amenbo
 * Antlion
 * Anton
 * Bata-pyon
 * Bigbom
 * Dango
 * Ga
 * Hotaru
 * Kabasira
 * Kama-Kama
 * Kamemusi
 * Kanabun
 * Kemusi
 * Kumo-Kumo
 * Mecha-Bu
 * [[W:C:sonic:Minomusi]|Minomusi]
 * Mosqui
 * Noro-Noro
 * Pata-Bata
 * Poh-Bee
 * Sasori
 * Scarab
 * Semi
 * Taga-Taga
 * Tentou
 * Tonbo
 * Yago

Sonic Chaos

 * Bane Motora
 * Tsuno-tsuno
 * Metal-o-Turtle
 * Frogger

Dr. Robotnik's Mean Bean Machine

 * Scratch
 * Grounder
 * Coconuts
 * Arms
 * Davy Sprocket
 * Dragon Breath
 * Dynamight
 * Frankly
 * Humpty
 * Sir F-Fuzzy Logik
 * Skeel

Sonic the Hedgehog 3

 * Batbot
 * W:C:sonic:BlastoidBlastoid
 * Bloominator
 * Bubbles
 * Buggernaut
 * Big Icedus
 * Catakiller, Jr.
 * Clamer
 * Corkey
 * Flybot767
 * Jawz
 * Tunnelbot
 * Flame Craft (Fire Breath)
 * Boling Spin
 * Mantis
 * Mega Chopper
 * Monkey Dude
 * Orbinaut
 * Penguinator
 * Pointdexter
 * Rhinobot
 * Ribot
 * Snail Blaster
 * Sparkle
 * Spiker
 * Star Pointed
 * Turbo Spiker

Sonic & Knuckles

 * Blaster
 * Butterdroid
 * Chainspike
 * Cluckoid
 * Dragonfly
 * Hei hou
 * Heat Arms
 * Madmole
 * Mushmeanie
 * Rock'n
 * Sandworm
 * Skorp
 * Spikebonker
 * Technosqueek - The Technosqueek first appeared as an enemy in Sonic & Knuckles. Here they zoom across walls, floors and ceilings and make no effort to attract the player. It reappeared as an enemy in Sonic Mania.
 * Toxomister

Sonic Triple Trouble

 * Bane Motora
 * Bombaberry
 * Bomblur
 * Mecha Hiyoko
 * Meta Junglira
 * Mosqui
 * Penguine Bombers
 * Rabibin
 * Spidal Tap
 * Sunset Park Badnik
 * Tidal Plant Badnik
 * Tart Turtle
 * Giga Thomas
 * Marve-shupopolous-gou

Sonic Labyrinth

 * Aroro
 * Dragogo
 * Flowawa
 * Gaikoko
 * Kabutoto
 * Kapupu
 * Kibaba
 * Mukaka
 * Nyororo
 * Ototo
 * Peppepe
 * Peroro
 * Puyoyo
 * Robototo
 * Takoko
 * Toriri
 * Yadokaka

Knuckles' Chaotix

 * Balru
 * Carry
 * Dribbler
 * Gotch
 * Happa
 * Juppun
 * Kameka
 * Nishita
 * Pata-Bata
 * Pirani
 * Uniformer
 * Zakku

Sonic R

 * Tails Doll
 * Metal Knuckles

Sonic Advance

 * Drisame
 * GamiGami
 * Hanabii
 * Kero-Kero
 * Kiki
 * Kura
 * Mirror
 * Mogu
 * Oct
 * Mecha Knuckles
 * Pen
 * Pierrot
 * Senbon
 * Slot
 * Tentou
 * Wamu
 * Yukimaru

Sonic Advance 2

 * Balloon
 * Bell
 * Circus
 * Flickey
 * Geji-Geji
 * Ghola
 * Hammerhead
 * Koura
 * Kubinaga
 * Kura-Kura
 * Kyura
 * Madillo
 * Mon
 * Mouse
 * Piko Piko
 * Star
 * Straw
 * Yado

Sonic Advance 3

 * Akatento
 * Ape
 * Bu-bu
 * Clam
 * Condor
 * Gaogao
 * Gekogeko
 * Ginpe
 * Guruguru
 * Hariisen
 * Jousun
 * Juggling
 * Kamaki
 * Kyacchaa
 * Marrun
 * Minimole
 * Muugaden
 * Takkon
 * Uutsubo
 * Yadokka
 * Yukigasen

Sonic Rush Adventure

 * Angler Fish
 * Cave Bat robot
 * Pirahna bot
 * Ptera
 * Steampacker
 * Tokrikeratanku
 * Wrench Swinger

Sonic the Hedgehog 4

 * Fullboar
 * Spikes
 * Steelion - In gameplay, Steelions are only encountered in White Park Zone Act 3. Here they will use the ice cold water to freeze them selves in an ice ball, blocking the player's route. Defeating a Steelion is very difficult as the player needs to time their attack to destroy it.
 * Zoomer
 * Scarbesque
 * Sandworm
 * Flamer
 * Snowy

SatAM and Archie

 * Pseudo Sonic

E-Series
The E-Series are a series of elite robots created by Dr. Eggman replacing the Badnik line.

Sonic Adventure

 * E-01 Baby Kiki
 * E-02 Rhino-Tank
 * E-03 Sweeper
 * E-04 Leon
 * E-05 Boa-Boa
 * E-06 Bladed Spinner (Spina)
 * E-07 Ice Bot
 * E-08 Kart Kiki
 * E-09 Buyoon
 * E-10 Cop Speeder
 * E-15 Spiky Spinner (Spiked Spina)
 * E-16 Electro Spinner (Thunder Spina)
 * E-17 Ghora
 * E-19 Egg Keeper
 * E-20 Kiki
 * E-22 Beat
 * E-24 Jetso
 * E-25 Duo Jet
 * E-26 Bomb Jet
 * E-27 Hyper Jet
 * E-28 Mecha Fish
 * E-29 Egg Pirate
 * E-31 Gola
 * E-32 Unidus

Sonic Adventure 2

 * E-1000

Sonic Heroes

 * E-1001 Egg Pawn
 * E-1002 Egg Flapper
 * E-1003 Cameron
 * E-1004 Klagen
 * E-1005 Egg Knight
 * E-1006 Egg Hammer
 * E-1007 Heavy Egg Hammer
 * E-1008 Falco
 * E-1009 Egg Bishop
 * E-1010 Egg Magician
 * E-1011 Casino Pawn
 * E-1012 Rhino Liner
 * E-1013 Rook
 * E-2000

Sonic Riders

 * E-10000G
 * E-10000R
 * E-10000Y

Sonic Free Riders

 * E-10000B (Turns out to be Metal Sonic.