Dragon Balls" which hurls fireballs diagonally downwards; and the "Invincible Fire Wheel" that creates a barrier of three fireballs around Ryu, destroying any enemy that touches them. These items can be found in various crystal balls scattered throughout the levels, and they can be switched out by collecting another Power Boosting Item. The amount of ninja power used depends on the type of Power Boosting Item used. At the end of each Act Ryu fights a boss which has its own strength meter, located on the top of the screen. The boss's strength meter decreases every time the player damages it, and the boss is destroyed when the player completely depletes its strength meter. Along the way, the player can collect items that are found in crystal balls scattered throughout the levels. These items include the following: items that increase Ryu's ninja power; bottles that increase the player's score; "Scrolls of the Spirit of the Dragon" that increase Ryu's maximum ninja power; medicine that partially refills Ryu's strength meter; Power Boosting Items; and 1-ups. Another new feature in Ninja Gaiden II is the ability for Ryu to "split his body" and clone himself when the player collects an orange ninja symbol. Collecting this symbol creates for Ryu an orange shadow of him that follows behind and copies every move Ryu makes, including climbing walls and ladders and attacking enemies. Using this technique, the player can strategically position Ryu and his clones to more easily defeat enemies and bosses. Release Electronic Gaming Monthly previewed Ninja Gaiden II in late 1989 and early 1990. The game first appeared in its September–October 1989 issue and again in its November issue; they noted the new levels, power-ups, and an "explosive story that's loaded with twists and turns". In the magazine's January issue, Steve Harris praised the game for its new power-ups, scrolling backgrounds, and more detailed cinematic cutscenes. He said that the game was going to take the series "one step further than before". The game was shown to the public for the time at the Winter 1990 Consumer Electronics Show in Las Vegas, in which Nintendo Power gave "four star ratings for its great cinema scenes and challenge". The same magazine previewed the game in its "Pak Watch" section in their March–April 1990 issue. They said that at first look the game had better cutscenes than the first Ninja Gaiden game, and they