Hyakkishu

Input:   (varied followup)

The Hyakkishu (百鬼襲, Hyakkishuu, "Hundred Demon Attacks"), also known as Demon Flip, is one of Gouken and Akuma's special attacks.

Description
Executed by performing a Shoryuken motion and one of the three kick buttons, the user leaps forward, high into the air. How far forward he travels is determined by the strength of the kick button pressed. There is an EX Special version of this move that automatically homes to the opponent's location, from any distance. The varied follow-ups, however, have the same properties irrespective of the button(s) used to perform the Hyakkishu or the follow-up itself.

Follow-Up
Depending on which attack button or buttons are pressed before the user lands, he will finish the move differently:

Hyakki Gozan
Input: 

If there is no follow-up command, the practitioner will perform the Gozan attack. Akuma does a sliding kick that trips an opponent, while Gouken does a sweep instead. This can be used to counter predictable projectiles patterns, but is extremely unsafe on block.



Hyakki Gosho (Akuma) or Goheki (Gouken)
Input: 

This attack differs between Akuma and Gouken; if a punch button is pressed before the user lands, Akuma performs a flying palmstrike, generally aimed at the opponent's head. This palmstrike has the Armor Break property and will also floor the opponent. In most games, this attack counts as an overhead and this cannot be blocked while crouching. Common jargon also refers to this move as the Demon Palm. Intentionally missing this attack and bufferinging two light punches during the landing animation also serves as a setup for the Shun Goku Satsu.

Gouken will instead parry, meaning that in this state he is considered to have Super Armor for a second or two. This "parry" means that if struck in this state, Gouken will not be stunned and will receive only the "provisional" damage that comes with Super Armor. The state lasts for the best part of a second, and if Gouken successfully parries, he will usually be able to counter-attack before the opponent can do anything further. As with any move with Super Armor, any Armor breaking move such as the Hyakki Gosho or EX Tatsumaki Gorasen can break through Gouken's defence.

Hyakki Gojin (Akuma & Gouken) or Gosen (Akuma only)
Input: 

From its debut in the Street Fighter Alpha series, to the title Capcom vs. SNK 2, following up the Hyakkishu with a kick input resulted in the Gosen. During this attack Akuma brings his leg crashing down on an opponent's head in a horizontal position, knocking him down for high damage, similar to the Gosho.

Starting from the Street Fighter III series however, a kick follow-up results in the Gojin instead, where the practitioner suddenly changes direction and does a downward angled kicked similar to the Tenmakujinkyaku, but with more hitstun and priority. This follow-up arguably has more utility than the Gosen, as it allows the attacker to immediately perform a combo upon connecting successfully. If spaced properly this move can even cross-up. Cosmetically, Akuma performs it in a fashion that is opposite of his Tenmakujinkyaku, while Gouken essentially replicates his. Gouken's version comes at a somewhat steeper angle making it harder to use as an ambiguous cross-up. The critical difference between Gouken and Akuma's versions (in Super Street Fighter IV: Arcade Edition Version 2012), is that Gouken's counts as an overhead while Akuma's does not.

Hyakki Gosai
Input: 

If both light punch and light kick (that is, a throw) are input before he lands, the user grabs his opponent and does a throwing attack. Akuma will grab the opponent's shoulders and flips them over, while Gouken grabs the opponent's head, performs a back flipping knee kick to the opponent's face, then slams the opponent down on the floor with a chopping attack.

In older games the Gosai throw is performed by pressing the relevant throw command, i.e. forward or back and strong punch or kick (or two punches or kicks in Street Fighter Alpha 3). Using the forward throw results in Akuma flipping the opponent upside down and driving them into his knee. Pressing the kick (i.e. back throw) will cause Akuma to put his opponent into a spinning pile driver similar to that of Zangief. This animation also makes an appearance in early Marvel vs. Capcom games if Akuma performs a double Hyper Combo with Zangief.

Hyakki Goho
Input: 

Executed by performing a quarter circle motion and a punch button, Akuma performs the Zanku Hadoken. In Super Street Fighter IV: Arcade Edition, starting from the 2012 patch, Akuma can cancel the EX Zanku Hadoken only from the EX Hyakkishu making it a somewhat costly follow-up that can be used to escape ground traps. However in Marvel vs. Capcom 3, Akuma can follow-up with a Zanku Hadoken of any strength from any Hyakkishu.