- Zombie - Corpses that have been revived by the energy of the Ghoul Realm. These hordes of living dead have no will of their own, and attack people in order to preserve their rotting flesh.
- Crow - The blue crow flys sideways in wavy patterns. The red crow targets Arthur, and flys directly at him.
- Green Monster - Reminiscent of a Venus Fly-Trap, this plant will bite players that get close to them and spit eyeballs from their throats.
- Blue Devil - These small devils are swift and agile creatures. They attack their opponents mischievously, as if playing some kind of game.
- Wraith - Also known as Woody Pigs, these are incarnations of pigs who wear tree stumps. These guardians of the woods appear abruptly and fly through the air, weaving back and forth.
- Goblin - Also known as Big Men. Although they lack armor of any kind, it takes many attacks to pierce their toughened bodies. They use all of their strength to launch projectiles at the enemy.
- Flying Knight - Armor haunted by the ghosts of knights who were slain by monsters. These unhappy spirits wander through the air, attacking any people that they encounter.
- Magician - Spell-using imp that changes Arthur into a form in which he briefly cannot fight. Similar to the Jester.
- Monster Tower - also known as a Golem, this creature of stone has the ability to come alive for brief seconds to shoot stone balls at Arthur. The Monster Tower has two heads, allowing it to shoot from the upper head, the lower head, or both.
- Unicorn Demon - At twice the size of Arthur, it commands massive strength. It has incredible jumping power, rising high into the air to land on and squash its opponents. Appears as the Stage 1 Boss, and as twin enemies for the Stage 2 Bosses.
- Dragon - It staggers enemies with its long body and spews fire from its gigantic mouth. The Stage 3 and Stage 4 Bosses.
- Satan - Satan is the one who, under Astaroth's command, swooped down and captured the Princess. He is a strong opponent who uses his swooping attack while hurling star projectiles. He can block any attack when he closes his wings. He will later work under Sardius, but only for a brief time. Appears as the Stage 5 Boss and as twin enemies for the Stage 6 Bosses.
Ghosts 'n Goblins is a platform game where the player must defeat zombies, demons and other undead creatures in order to rescue the princess. Along the way the player can pick up new weapons, bonuses and extra suits of armor that can help in this task. The game is often considered very difficult by arcade standards, and is commonly regarded as one of the most difficult games released for the NES.
The player starts out with three lives, and is awarded an extra life when the player reaches 20,000 and 70,000 points. A further life is awarded at every 70,000 points after that. Two hits from an enemy attack will result in a life being lost. After the first hit, Arthur is reduced to his boxer shorts. A second hit turns him into a skeleton. At the start of each level, Arthur is dressed in full armor whether or not he had armor at the end of the previous level. At certain points in the game, Arthur can suffer instant death whether he is suited in his armor or not.
If the player loses a life, he is returned to the start of the level, or the halfway point if he has managed to get that far. Furthermore, each life can only last a certain length of time (generally around three minutes), the clock being reset at the start of a level. If the clock does run out, the player instantly loses that life.
- The famed Yashichi makes yet another Capcom appearance in this game. In the NES version, it nets the player 5000 points if it glows solid red. Other times, depending on the placement and level at which the Yashichi is collected, it grants the player additional time. However, if the Yashichi glows green as well, it will subtract time from the timer.
Programming: Mark Fitt
Additional: Alex Amsel
Producer: Troy Sheets
Music: Allister Brimble
Art: Richard Whittall
Special Thanks: Freya Shephard
Capcom: Jim Wallace, Bert Schroeder, Mark Rogers
Testers: Russell Young, Gene Sprague