This is a list of the areas that appear in Jack Bros..
Area 1: Forest of FairiesEdit
The boss of Forest of Fairies is Lamia who pops out of holes in the floor and fires projectiles.
Area 2: Grim Reaper's Cavern (死神のほら穴)Edit
The Grim Reaper's Cavern consists of floors 04-08. In this area, the Tomcat and Elf begin to appear as enemies. Elf is a ranged attacker using a bow.
Jack Traps are introduced as spiked sections of the floor that will rise and fall at specific intervals. Boulders are also added as movable obstacles.
The boss of the Cavern is Sinister Scar. Scar is a skull that fires projectiles while moving. When it stops, a snake will emerge to attack the player.
Area 3: Temple of Nightmare (悪夢の神殿)Edit
The Temple of Nightmare covers floors 09-15. It adds the Paradice as a moving trap that will catch players in between them and Warp Tiles that will change a player's position on the map as well as return the boulders to their original positions.
Mystic Morgan, Furin, and Poltergeist are introduced as enemies on this level. Mystic Morgan teleports before attacking. Furin carries a shield and must be attacked from the side or behind. Poltergeist teleports until it is trapped in a corner where it can be killed. Poltergeist will drop a clock that adds 50 seconds to the level clock.
Vampire is the boss of the Temple of Nightmare. He mainly fights by shooting projectiles. The boss area, however, is made up of conveyor belts that will regularly shift direction.
Area 4: Dragon's Belly (地竜の体内)Edit
Dragon's Belly covers floors 16-25. It adds the Double Lasers, a pair of lasers that shoot beams at each other. They must be destroyed from the side or blocked with boulders. This area also introduces Dark Zones, which are areas where the player will not be able to see, leaving them open to enemy attacks. Keys in the Dark Zone will still appear on the player's mini-map. Firebreathers are the final obstacle that begin to appear in this area. They will regularly fire a blast of flames in a straight path. Flames can be blocked just like lasers.
This area is also where Skelipede becomes an occasional enemy, moving through the map while shooting projectiles. He must be attacked from the head to kill him. Luminous Lex is also introduced here as a moving, indestructible laser that must be dodged or blocked.
The boss of Dragon's Belly is Spider Orb, who must be hit in the eye which he will shift his legs in front of to protect. He fires star-shaped projectiles that can stun the player if they hit.
Area 5: Mecha Fortress (機械城)Edit
The Mecha Fortress covers floors 26-40. Angel is introduced in this area as enemies that will spawn off the map itself and shoot a ball and chain to attack the player. The player must hit the ball and chain in order to defeat them. Cyclops also appears as an enemy that can cause screen-wide earthquakes. He requires several hits to kill.
Wybern is the final boss of this area who attacks with a wide-reaching stream of fire. This boss area is also covered in Jack Traps that will move row-by-row.
Area 6: Crystal Palace (水晶の神殿)Edit
The Crystal Palace is the final area of the game consisting of floors 41-60. It adds no new enemies or traps until the boss floor where Belzoff spawns. After defeating his first form, he will spawn in his fly form where he shoots multiple projectiles and flies.