Wario Land 4

Wario Land 4, known as Wario Land Advance: Yōki no Otakara (ワリオランドアドバンス ヨーキのお宝) in Japan, is a video game released for the Game Boy Advance system in 2001. In this game, Wario has to gather four treasures to unlock a pyramid and save Princess Shokora from The Golden Diva. It features 2-D graphics with linear transformations (similar to Yoshi's Island).

Plot
The manual describes how Wario is reading the newspaper when he notices an article about a mysterious pyramid found deep in the jungle. The legend related to the pyramid is that of Princess Shokora, ruler of the pyramid, who was cursed by the money-crazed Golden Diva.

Without wasting time, Wario jumps into his Wario Car (as shown in the opening animation) and speeds toward the pyramid. As he enters it, he finds a black cat and chases it. Doing so, he falls down a precipice and is stuck inside the pyramid.

After fighting his way through the entry passage and an early boss battle against Spoiled Rotten, Wario discovers four new passages. After completing these passages, Wario gains access to the innermost part of the pyramid, which ends up being the stronghold of Golden Diva. Wario meets the cat again, who turns out to be Princess Shokora.

Wario defeats Golden Diva and exits the pyramid with all his treasure and Shokora, who gives Wario a kiss on the cheek and disappears of which the appearance differs depending on the amount of treasure that has been retrieved. Wario leaves the pyramid triumphantly. If the player beats every level with 10,000 coins, and has all treasure chests after beating the diva, they will unlock a special ending which involves Wario with even more money.

Gameplay
The gameplay of Wario Land 4 (which is generally similar to that of Wario Lands 2 and 3) 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, Topaz, Ruby, 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 music in the CD Room.

Upon entering a level, one has unlimited time 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 Wario fails to reach the portal within the time limit, he begins to lose coins. Once all of his coins are gone, he is kicked out of the level (as if he had lost all of his health) and is left with no treasure.

At the end of each passage, Wario encounters a boss room. He must destroy a boss within a set time limit to win the treasure within the boss rooms (if Wario takes too long but manages to win before the limit is up, some treasure may be withheld). Before each battle, Wario will enter a hall way consisting of two doors. One is a shop which uses mini-game coins as currency; in it, Wario can buy various power-ups and weapons that deal damage to the boss right before the battle.

Reception
IGN gave Wario Land a 9 out of 10, or "Outstanding", citing its well thought out level design and replayability, though the game does not significantly push the performance power of the Game Boy Advance.