The Lion King is a side-scrolling platform game based on the Disney animated film of the same name. The version for Sega's Game Gear is based on the 16-bit version and has the same general gameplay and level themes, but its own level designs and other differences. The player controls Simba through ten levels, all based on locations from the film. In the first six levels, Simba is a cub, while in the seven following levels he becomes an adult. The two forms differ slightly in abilities: young Simba can roll sideways, damaging enemies that are in his way. As an adult, Simba can slash enemies directly with his paws, while both can use their roar to temporarily stun and jump on top of enemies to defeat them.
In most levels, various power-ups can be collected, many of which come in the form of bugs. These include health restoration, temporary invincibility, and upgrades for Simba's roar and slash. Other items to collect are extra lives and continues as well as diamonds, which enable the playing of a bonus round after finishing a level.
In the bonus round, the player controls Pumbaa, who must catch melon seeds falling from the top of the screen. For every ten seeds collected, an extra life is awarded at the end. Accidentally catching bugs removes seeds, however.