For those who have never fought Evil Ryu and Oni in Super Street Fighter IV: Arcade Edition via arcade mode, here are the tips:
For Evil Ryu
Get at least one perfect win in a round (it’s possible bonus
stages may count perfect wins even you have completed one); especially
from the start.
Never lose a round and use continues. However, during the fight
against Seth, if you have any hard time fighting him and you lost a
round, you may still have a chance, for as long as you finish him with a
super or Ultra combo.
Beat Seth with a Super or Ultra Combo.
For Oni
Get at least one or two perfect wins in a round (bonus stages
may have a probability of counting perfect wins, even if you completed
one of the two bonus stages), especially from the start.
Get at least five first attacks.
Never lose a round and use continues
Three Ultra Combo Finishes.
Beat Seth with a Super or Ultra Combo.
If one has achieved these following requirements after beating
Seth, the said two bosses will appear in accordance to the requirements
met.
The Shin Shoryuken (真・昇龍拳, "True Rising Dragon Fist") is a special attack that made its debut in the Street Fighter Alpha series as one of Ryu's Super Combos. The move was taught to him by Gouken, who uses it as an Ultra Combo in the Street Fighter IV series, though it was previously implied in the Street Fighter Alpha series to have been discovered by Ryu on his own.
The
attack itself is the manifestation of its namesake, the "true"
technique of the Shoryuken. The user strikes the opponent very hard in
the midsection (via elbow or punch), and then performs a high-damage
Shoryuken. This requires the utmost focus and temperament to perform
correctly. If the user misses the initial mid-section attack, however,
they will just perform a Kinjite Shoryuken,
a Shoryuken which has multiple hits and acts as a failsafe; it is
capable of hitting the opponent should they jump away to avoid the
attack.
Ryu strikes the foe's midsection with his closer elbow, uppercut the
foe with his other hand, and then perform a powerful Shoryuken with the
closer hand.
The move has the same command as the Metsu Shoryuken;
the difference between the two is the distance from the opponent, with
the Shin Shoryuken requiring Ryu to be a bit further away from the
target at a certain distance.
Street Fighter III series
Ryu punches the foe in the midsection instead with a Shoryuken, and
if that connects without Ryu leaving the ground, he then uses his other
hand to perform a 3-hit finishing Shoryuken.
Gouken's
version is the same as Ryu's from the previous series, indicating that
he taught Ryu the move. When performing the move, Gouken says "Got you!"
upon landing the initial attack, "Shin!" upon delivering a powerful
alternate-handed uppercut to the opponent's jaw, and "Shoryuken!" as he
performs that very move, sending them skyward.
Ryu elbows the foe with his left arm, and performs a multi-hitting Shoryuken with the other arm.
Street Fighter X Tekken
The move appears in the game as Ryu's EX Shoryuken, and is performed the same exact way as it was in the Street Fighter III series.
In Fanfiction
In the fanfiction crossover with Street Fighter and Mai-HiME by TheEternalRival in fanfiction.net, in the third chapter of the story, Natsuki was defeated by Ryu with the Shin Shoryuken. In the chapter 9of the said story, Natsuki is later revealed to learn this move, despite she has signs of weakness against it. Natsuki's version of the Shin Shoryuken alludes to Ryu's version seen in Marvel vs. Capcom 3.
Natsuki's fist is shown to be surrounded with ice before performing the move.
Tactics
In the Street Fighter IV games, Gouken is able to fully use this Ultra flexibly, as it has armor breaking properties, a very good horizontal range, a good anti-air and in terms of damage, and - with a full Revenge Gauge
- does around half a health bar's worth of damage. As a boss, Gouken's
Shin Shoryuken has a quicker startup and much greater priority.
Generally, if timed incorrectly and/or the opponent blocks/avoids
the attack completely, the opponent can easily punish the user; the
after-lag for the Kinjite Shoryuken is higher than that of the fierce
Shoryuken used by Ryu, Ken, and Akuma.
Asura from Asura's Wrath uses this move in his fight against Augus.
Yuri Sakazaki of the Art of Fighting and King of Fighters series parodies this technique in the form of her Shin! Chou Uppaa! (True! Super Upper!) move.
Executed by performing two quarter-circle forward motions and pressing punch (in the Street Fighter III series) or all 3 punch buttons (in Super Street Fighter IV),
Yang adopts a snake-style kung fu stance ("I'll show you!") then
dashing forward with a hand thrust. If this connects, he will twist his
hand and swipe it upwards, knocking the opponent up into the air
slightly.
What happens next depends on the version. In the Super Art, he
will immediately finish the combo by dashing past the opponent with a Tourou Zan movement, hitting multiple pressure points as he does and inflicting sizable damage. This final dash can be compared to the Zan'ei art that his martial arts teacher, Gen, uses.
In the Ultra Combo, he follows the upward swipe with a smaller
Tourou Zan that leaves him on the far side of the opponent, then a
vertical Tourou Zan, then a jumping, flipping hand slash which hits
multiple time, another Tourou Zan which leaves him on the original side
that he started on, and finally the dashing pressure point strike from
the Super Art version ("Looks like you couldn't avoid that one!").
In Fanfiction
In my fanfiction crossover story Street Fighter X Mai-HiME, Yang still uses this as one of his Ultras. And Natsuki Kuga manages to learn this move as of chapter 17 of the said story; the move's animation for Natsuki's Raishin Mahhaken is still the same as Yang's version seen in Super Street Fighter IV: Arcade Edition. Let's not forget this Ultra Combo is Shizuru Fujino's weaknesses.
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