????·?????????????!

Jack Bros. follows three Jack brothers: Jack Frost, Jack Lantern, and Jack Skelton, who have crossed from the fairy realm into the human world through a portal that opens each year on Halloween. They lose track of time and realize too late that they must return before the portal closes. With only one hour left, the fairy Pixie guides them to a perilous shortcut. This dangerous route is their only hope to make it back to the portal in time.

The player chooses one of the three Jack brothers to control, with Pixie also available as a unlockable character. The goal is to navigate through six distinct areas within a strict time limit to return to the fairy world before the portal closes. Each area is made up of several floors. To progress to a lower floor, the player must collect all the keys on the current floor. A radar helps locate the keys and, once all are gathered, it reveals the exit's location. At the bottom floor of each area, a boss awaits, and defeating this boss is required to move on to the next area. To defeat enemies, the player can utilize both regular and special attacks. Special attacks consume Special Attack Stars, of which the player begins with three but can acquire more throughout the game; these stars are retained as they progress through different areas.

Each character has unique attacks: Jack Frost throws snowballs, Jack Lantern shoots fireballs, and Jack Skelton wields a knife. Their special attacks vary: Jack Frost can freeze all enemies for a few seconds, Jack Lantern inflicts massive damage to all enemies, and Jack Skelton can eliminate all visible enemies on the screen. While exploring the floors, players must avoid enemy attacks and traps, as each hit or trap triggers a five-second reduction in the time limit. If the timer runs out, the game ends, but players can restart from the beginning of the current area.