The gameplay of Wario Land 4 allows for some open-endedness as well as some order of difficulty. There are four main passages in addition to the Entry Passage and "Final" Golden Pyramid: the Emerald, Ruby, Topaz, and Sapphire Passages, in order of difficulty. The Emerald Passage is themed around nature. The Ruby Passage is themed around mechanics and technology. The Topaz Passage is themed around toys, games, and other "playtime" ideas. The Sapphire Passage is themed around horror and danger, prominently involving ghosts and the like.
There are four levels in a passage. To progress to the next level in a passage, a player has to find the Keyzer in the previous level (a Keyzer is a floating key-nosed creature that promptly disappears after the player uses it). After the four levels comes a Mini-game Shop and the Boss Room. To enter the Boss Room, the player must find the four pieces of the passage's namesake gem in each level (a total of four gems and 16 pieces). Also, a player can find a CD in each level, which unlocks a song in the CD Room.
Wario as he explores the game's first level, Hall of Hieroglyphs, in the Entry Passage.Upon entering a level, one has all the time in the world they want to find treasure, beat up enemies, and such. Enemies, when defeated, give coins and health orbs. After collecting a full bar of health orbs, the player receives one extra heart (out of 8). However, the player can't return to the pyramid (and thus have all of their treasure saved) until they open the portal again via a Frog Switch. Upon hitting the switch, a time limit (which varies depending on the game's difficulty setting and level itself) is placed, and many blocks in the level appear or disappear. For some levels, this results in a rush back to the portal the same way the player came. In others, totally new areas are exposed. If a player fails to reach the portal within the time limit, he begins to lose coins. Once all of his coins are gone.