Please note that this is the Reborn Wiki's article on Shigure Soen Ryu, the sword style. If you are looking for the article on Shigure Soen Style, the 108th Reborn! manga chapter, then you should head to Shigure Soen Style.
The Shigure Soen Ryu (時雨蒼燕流, lit. "Shower in Late Autumn, Blue Swallow Style) is a sword technique that is called the "Invincible Sword Style" for several reasons. This technique originated with one man, and like a family tree, it grew. As the technique was passed down, the more the tree grew. It is common for a generation to add a new form to the Shigure Soen. This is a sword style that varies, depending on who your master was. Thus, there could be many different variations of the Shigure Soen Style.
Shigure Soen is used by three people in the series. Takeshi Yamamoto, Tsuyoshi Yamamoto, and Squalo.
The Shigure Soen Style is a notoriously deadly sword style that is only passed down to worthy successors. Each 'form' of the style is only shown once to the student - if the student is worthy to succeed, he only needs to see it once to remember how to use it from then on. It originally only had one form that was passed down through generations of successors with each successor creating and adding their own forms resulting in many branches of Shigure Soen Style. However, as new forms were created, the weaker branches deteriorate, and others disappear as there is no worthy successor; hence, this style can be called the perfect, flawless style.
The Shigure Soen Style taught to Yamamoto consists of 8 forms; four defensive (守式, Shushiki ), four offensive (攻式, Koushiki).
1 Shajiku no Ame 車軸の雨 (Axle of Rain) - Offensive. Yamamoto charges forward and attacks with a thrust.
2 Sakamaku Ame 逆巻く雨 (Rolling Rain) - Defensive. Yamamoto lifts waves of water around him, and then ducks, putting his sword protectively in front.
3 Yarazu no Ame 遣らずの雨 (Last Minute Rain) - Offensive. Yamamoto drops the katana, kicking it with his foot, to send it flying in a stab.
4 Gofuu Juuu 五風十雨 (May Wind, October Rain) - Defensive. Yamamoto synchronizes with his opponent's breathing to evade attacks.
5 Samidare 五月雨 (Early Summer Rain) - Offensive. Yamamoto slashes diagonally but in midway he drops the sword, switching hands, before finishing the attack.
6 Unknown, deducted to be defensive.
7 Shibuki Ame 繁吹き雨 (Splashing Rain) - Defensive. Yamamoto holds the sword backwards and spins to create a whirlwind like shield.
8 Shinotsuku Ame 篠突く雨 (Pelting Rain) - Offensive. Yamamoto uses the blade of the sword to cut around the bearer. Yamamoto can also use Rain Flames with this move if there's no water. An alternative version was used by Future Yamamoto with hot water called Shinotsuku Nettou.
9 Utsushi Ame うつし雨 (Duplicate Rain) - Offensive. Yamamoto makes a tidal wave with his sword and, while his opponent is distracted by his reflection, he attacks from above.
10 Scontro di Rondine 燕特攻 (Clash of the Swallow) - Offensive. A tidal wave of Rain Flames surrounds him while he charges, led by the Swallow from his Box.
11 Beccata di Rondine 燕の嘴 (Swallow's Beak) - Offensive. Yamamoto thrusts his blade multiple times with one hand.
Aggregate Art: Jiunoka 時雨之化 (Rainy Metamorphosis) - Defensive + Offensive.Yamamoto combines all his forms to strike moving objects with rain flames, causing them to slow down to the point that they appear to be frozen in place.
12 Sadachi: Kirisame(Brazen Left Blade: Drizzle)- Offensive. Yamamoto uses the Jirou left sword of his Cambio Forma Version Vongola Gear to attack with multiple compressed airwaves which can "Sniff" out an enemy, making this perfect against illusionists.
12 Udachi: Kirisame(Brazen Right Blade: Cutting Rain)- After Sadachi: Kirisame, this attack is different in that the waves are shaped like Kojirou and can cut the opponent who has been "Sniffed" by Jirou.
An alternative 8th form that was created by the Shigure Soen Ryu user who was defeated by Squalo and was Yamamoto's dad's fellow apprentice, is called Autumn Rain.
Both Forms 10 and 11 have an amazingly strong resemblance to Squalo's attacks in the Rain Ring Battle, (Fang of the Shark, Charge of the Shark). It is highly possible that this is where Yamamoto conjured the idea of his own forms.
Future Yamamoto could perform many of Squalo's techniques, and while the present Yamamoto has not been seen directly using the techniques, he has been seen using them within Shigure Soen. For example, when he strikes Genkishi with a form, he unleashes Attacco di Squalo at the same time.