Based on characters from Fisher-Price's Rescue Heroes toy line, Fire Frenzy involves saving a national park from the ravages of fire in a series of five levels. Each level features a different character whose goal is to put out the fires or to rescue stranded victims. Team leader Billy Blazes uses a fire hose, for example, to douse smoldering bushes in a game patterned after concentration. Behind each bush hides a forest animal, which players match to another animal until an identical pair is made.
Rip Rockefeller uses a front-loader to dig a firebreak spanning the entire screen while avoiding boulders in a maze-like forest, while Jake Justice zips across the screen in his motorcycle to rescue stranded park visitors. Gil Gripper hops aboard his watercraft to carry people from one side of the park to the other, and Ariel Flyer extinguishes a series of fires from her helicopter before returning to pick up town residents. Completing each task in order opens up a bonus game with astronaut Roger Houston.
From his spaceship high above the area, Houston must warn his team about another fire starting in the park. This involves sounding an alarm by repeating various directional and button presses to follow the correct sequence. Once complete, the game continues on a more difficult setting until the player receives all four promotions from Rookie to Specialist. Completing each level also earns players badges, which can be printed out using the Game Boy Printer and colored.