Wario returned to the Nintendo Game Boy in 1998 in the sequel to the popular Super Mario Land 3: Wario Land in Wario Land 2. There were two versions of this game released. The first came in March 1998 for the Super Game Boy, while the second came in October 1998 for the Game Boy Color. The only difference in the two versions was that, obviously, one was in color while the other was limited to the SGB's limited color array. Both versions feature a battery for saving progress.

The story begins as Wario, sleeping in his grand castle that he bought in the previous game, is robbed by Captain Syrup and the Brown Sugar Pirates! With all his hard-stolen coins absconded, Wario sets off to reclaim his fortune and teach the pirates a lesson. In order to do so he'll have to complete the various objectives across a wide variety of levels including places set in the sea, forest, city, and even Wario's own castle grounds.

The unique aspect of this game is that Wario cannot be killed. He is invincible. Over the course of the game he is squashed, stabbed, burned, and stung and yet he keeps coming back for more without a dent in the fender. There are no bottomless pits to fall into, nor is there a timer ticking away precious seconds. Dangers that would zap any ordinary video game hero merely cause Wario to transform into a different form that he can use to overcome obstacles. For example, being squashed by a large weight causes Wario to flatten out into a thin sheet. He can then fit into narrow passages. Being set on fire turns Wario into a living flame capable of burning through brittle wood. All of the transformations are easily reversable.

In addition to collecting coins Wario has to find the hidden treasure in each level. The treasure is locked away in a chest that can only be opened if Wario wins the mini game presented. In the mini game a picture of an enemy is shown, then eight cards are briefly turned over to reveal a glimpse of what enemy is on each card. Then the player must match the two enemy cards. If a match is made, Wario gets the treasure. Failure to match means Wario has to play again at the cost of some hard earned coinage.

The game can branch out in multiple directions based on Wario's actions and inactions. For example, the game begins with Wario asleep in bed. Moving the control pad causes Wario to wake up and play the level, but allowing Wario to sleep results in the Brown Sugar Pirates kicking Wario out of the castle and into another level. There are several branching points such as this is various points in the game. Some are hidden and some are not. Exploration is the key to finding them all. At the end of each level Wario can play (at the cost of some coins) a puzzle game in which a 3x3 grid of white squares is gradually turned over to reveal a number. Guess the number being revealed and win a piece of a treasure map. Earn the entire map to access a hidden mini game.

Wario Land 2 is a stellar adventure and worthy of some attention. The Super Game Boy version is hard to come by these days, but the Game Boy Color version is still plentiful in stores. The game was such a success that it spawned two sequels, Wario Land 3 and Wario Land 4.