Hadouken
Hadouken or hadoken (波動拳, hadōken?, a Japanese neologism, literally "wave motion fist" or "surge fist"), is a special attack used by Ken, Ryu, Dan Hibiki (whose version of the technique is named the Gadouken), Akuma (Gou Hadouken), Sean (Hadou Burst), Allen (Soul Force), Kairi (Shinki Hatsudou) and Gouken (also called the Gou Hadouken). Takashi Nishiyama, the creator of Street Fighter, credits the 1970s anime Space Battleship Yamato and a missile called the Hadouho as the origin of hadouken. The hadouken and the shoryuken are the two archetypal moves of these characters. The move is achieved by the character thrusting their palms forward, sending a surge of spirit energy (or ki) flying towards the opponent. It is normally performed by the player moving the joystick or D-pad a quarter circle forward towards the opponent from the down position, then pressing a punch button (so, for example, a character facing to the right would execute the move by pressing ↓, ↘, →, and then "punch" in a smooth motion).
Most fighting games of the sprite-based era used projectile special moves, and while the actual type of projectile launched varies from game to game and character to character, the execution and behavior of these attacks are often rather similar to the Hadouken. These moves are sometimes informally referred to as a "hadouken", or fireball. The Hadouken can usually be performed in three different degrees depending on which type punch is used; these will affect its speed, damage caused on impact, amount of recovery frames, and sometimes its range. The Hadouken itself has many variations depending on the character in question that the move is associated with. For example, both Ryu and Akuma have used a fire-based variant of the move called the Shakunetsu Hadouken (灼熱波動拳) or "Blazing Surge Fist", which briefly engulfs its target in flames. Another variant that appears is the ability to execute a hadouken whilst in the air which travels diagonally down and forward.
Later titles in the series that use super combo moves ramp up the power of the hadouken, evolving it into the Shinkuu Hadouken (真空波動拳 - Vacuum Surge Fist). This takes one of two forms depending on the game: an outsized fireball, or a blast of constant energy. Street Fighter III introduced the Denjin Hadouken (電刃波動拳), an unblockable, electrified version which could be 'stored' by holding down the Punch button, for timing purposes as well as enhancing damage and stun. In Super Street Fighter IV, Gouken can perform this technique; it is blockable, but will still inflict stun damage even if blocked. In the Capcom vs. SNK series, Evil Ryu used a more powerful version called Metsu Hadouken (滅波動拳), which acted similar to Denjin Hadouken, being unblockable and stunning the opponent. The latest game in the series, Street Fighter IV, brought back the Metsu Hadouken, though it instead acts simply like a more powerful variant of the Shinku Hadouken.
Interestingly, the Hadouken ability appeared in Mega Man X and its remake Mega Man: Maverick Hunter X as a secret move for X. It is only obtainable by having all heart tanks, sub tanks, weapons, and upgrades, (other requirements differ between the two games). The input is the same as in Street Fighter. This move can kill almost anything instantly, with the exception of several bosses. Even these, however, could be killed with two Hadoukens (although the final boss can be defeated with a single hit in the remake). In Mega Man X4, one of the bosses, Magma Dragoon, used the Hadouken ability. Another version of the Hadouken was created in Mega Man X: Command Mission, where if one is able to meet the secret boss(es), the Tails Clan in a battle, the Tails could throw the Annihilator Hadouken at them. It is a beam-like blast that hits all characters and causes massive damage, most of the time K.O.ing most characters. In Mega Man Xtreme and its sequel, a fighting style "Shotokan" can be acquired and allows X to use the Hadouken and the Shoryuken.
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