Using some of the environment in this manner, as well as attacking or destroying certain objects, serve as a puzzle-solving element to unlock secrets in the game. The environment plays a vital role in the game, as there are several hazards that will instantly kill an enemy, such as pits in the floor or rotating wheels of spikes. These are mainly gained through defeating opponents, with the combo system multiplying the value. Combos and special moves are upgradeable through the earning of experience points. The main characters also have many of their signature moves from the series. The engine allows the player to maintain combo attacks across multiple enemies, and even continue their combos after launching an enemy into the air through a powerful attack or a throw. Shaolin Monks features a multi-directional combat system, which gives players the ability to attack any of the enemies that surround them fluidly. Scorpion and Sub-Zero are also unlockable playable characters in the game. Tokens can be found throughout the game which will unlock some of these characters in versus modes. Some are there to aid the main characters, including Raiden, Johnny Cage, and Sub-Zero, while others serve as the game's bosses, including Mileena, Reptile, Scorpion and Shao Kahn. In addition to Liu Kang and Kung Lao, the game features other characters from the Mortal Kombat series. In addition, players can play a shortened, censored demo version of "The Suffering: Ties That Bind" as well as an emulated version of Mortal Kombat II. There is also a versus mode, where two players can fight against each other in some of the arenas featured in the game. Aside from a single-player mode, the game has a co-operative mode, where two players can work together through the game, with access to some areas and items that are inaccessible in single-player mode. The game features three main modes of play. But the sorcerer is not the only person who wants Earth the Emperor of Outworld, Shao Kahn, wants Earth for his realm and he will stop at nothing until he gets it. Throughout their journeys, they are joined by a mysterious princess named Kitana, meet familiar foes and eventually save Sonya and stop Shang Tsung. They are guided by Raiden and assisted by Johnny Cage. The Shaolin Monks, Liu Kang and Kung Lao, journey through the nightmarish realm of Outworld to stop the sorcerer's plot. If successful, Shang Tsung will conquer Earth without winning a Mortal Kombat tournament, which is cheating. Raiden confirms that Shang Tsung is trying to lure Liu Kang and his allies to Outworld where he can order his henchmen to attack them and bide his time for power. The Tarkatans are defeated, but Baraka captures Sonya Blade. Upon arrival, they meet Baraka and the Tarkatan attacking the Wu Shi Academy. Liu Kang and Kung Lao, however, have to fight their way to another portal to get to Wu Shi Academy. Everyone, except Liu Kang and Kung Lao, evacuates and escape back to the Wu Shi Academy. Raiden appears afterwards and warns the remaining fighters to get off the island palace because it is collapsing into the sea. With Goro distracting everyone else, Shang Tsung creates a portal to Outworld and retreats. The Shaolin monk Liu Kang defeats Shang Tsung, and the giant Goro comes to his defense. The battle raged furiously on Shang Tsung's island fortress in the Lost Sea, as the sorcerer watches from his throne. The game centers on two members of the Shaolin Order, Liu Kang and Kung Lao, as they travel through the realms in an attempt to thwart Shang Tsung's plans to dominate Earthrealm. Shaolin Monks is an action-adventure game that spans the events of Mortal Kombat II, starting with the aftermath of the first Mortal Kombat.