The Wizard of Oz is a re-telling of L. Frank Baum's classic story, strongly influenced by MGM's 1939 musical. To a lesser degree, individual levels adapt locations from the 1993 Wizard of Oz animated series by DIC, using settings from the series, such as Time Town.
The game is a platformer that encourages exploration. The action is split into four worlds. In each of the first three worlds, the Scarecrow, Tin Man, and Lion can be found and controlled by the player. After gaining a companion, the characters may be switched on the fly, each companion having significantly different attacks and abilities. Several of the levels require using a combination of all of these abilities to fully explore. The game also includes a variety of mini-games which gives the player a chance to play as the dog Toto as well.
All levels can be revisited once passed. Doing so serves the purposes of stocking up on items and finding the Emerald City tickets, which are required to enter the final area.