Below are the different campaigns in the game which you will encounter by travelling the Yellow Brick Road along with a list of the enemies you will encounter there.
Munchkin Town (Munchkin Country)
Rat King
Armored Spider
Imperial Ranger
Imperial Guard
Imperial Knight
Rat
Rat King
Dark Elf Magician
Winged Monkey Cleric
Winged Monkey Assassin
Winged Monkey Hunter
Winged Monkey Cleric
Winged Monkey Assassin
Chiss
Dragon
Dark Elf Swordsman
Dark Elf Magician
Winged Monkey Brigade Leader
Wicked Witch of the East
The Countryside (Munchkin Country)
Dark Elf Huntress
Dark Elf Swordsman
Dark Elf Shadesinger
Dark Elf Magician
Spider
Rat
Rat King
Winged Monkey Brigade Leader
Kalidah Brute
Kalidah Hunter
Kalidah Beastguard
Kalidah Spiritcaller
Kalidah Sorcerer
Chiss
Tik Tok
Winged Monkey Cleric
Armored Spider
Lady Ann Soforth
Toxic Spider
Huxtable
The Eight-Legged King
The College (Munchkin Country)
Winged Monkey Brigade Leader
Winged Monkey Assassin
Wicked Witch of the East
Winged Monkey Cleric
Coven Witch
Coven Disciple
Gargoyle Skyblade
Gargoyle Stormlord
Gargoyle Ripper
Gargoyle Axethrower
Imperial Knight
Imperial Ranger
Imperial Guard
Imperial Commander
Clifftop Wyrmling
Kalidah Brute
Rat
Rat King
Spider
Toxic Spider
Armored Spider
Dark Forest (Quadling Country)
Jack Pumpkinhead
Armored Spider
Dark Elf Magician
Dark Elf Swordsman
Dark Elf Night Axe
Kalidah Beastguard
Coven Temptress
Kalidah Sorcerer
Kalidah Spiritcaller
Kalidah Brute
Toxic Spider
Armored Chiss
Chiss
Winged Monkey Assassin
Winged Monkey Cleric
Winged Monkey Brigade Leader
Fen Wyrmling
Dark Elf Huntress
Dark Elf Shadesinger
Rat
Rat King
Spider
Porcelain Province (Quadling Country)
Lady Ann Soforth
Iron Wyrmling
Gargoyle Ripper
Gargoyle Skyblade
Gargoyle Axethrower
Gargoyle Stormlord
Porcelain Magician
Porcelain Solder
Winged Monkey Brigade Leader
Winged Monkey Cleric
Winged Monkey Hunter
Winged Monkey Assassin
Coven Temptress
Chiss
Armored Chiss
Dark Elf Swordsman
Dark Elf Magician
Imperial Guard
Imperial Ranger
Imperial Commander
Rat
Rat King
Tik Tok
Glinda's Castle (Quadling Country)
Aujah
Audah
Aurah
Porcelain Magician
Porcelain Soldier
Coven Temptress
Coven Witch
Coven Disciple
Fen Wyrmling
Clifftop Wyrmling
Iron Wyrmling
Dark Elf Huntress
Dark Elf Night Axe
Dark Elf Magician
Dark Elf Shadesinger
Kalidah Beastguard
Kalidah Brute
Kalidah Hunter
Dragon
Armored Spider
Toxic Spider
Armored Chiss
Toxic Chiss
Gargoyle Ripper
Gargoyle Skyblade
Gargoyle Axethrower
Gargoyle Stormlord
Huxtable
The Eight-Legged King
Emerald City (In the center of the land of Oz)