Egg Mania is a puzzle game where you control an egg-shaped character against either a computer opponent or another player via the link cable. The goal is to build a tower tall enough to reach a balloon at the top of the playfield before your opponent does. If you try to take shortcuts, your structure will start crumbling and water will come up faster. There are many obstacles, including falling meteors and bombs from your opponent.
The game has several modes: Over Easy and Hard Boiled, which differ in difficulty. There are also four extra modes: Survival, Solo, Time Trial, and Bomb. In Survival, you must survive as many rounds as possible. In Solo, your goal is to increase your overall score by completing rows and performing combos. Time Trial challenges you to beat your own best time. Bomb mode ends when the opponent's tower is destroyed.
The console versions have improved graphics and sound compared to the GBA version. They also feature cutscenes at the beginning of each level, a wider play area, and two additional modes: 8-player Tournament and Custom. However, they lack the Time Trial mode.