If you're watching One Piece, you must be familiar with a technique called Shigan, aka finger bullets. This technique is one of the strongest techniques mastered by Rokushiki users, such as CP9 or CP0 agents.
Interestingly, Shigan can be used in various ways or methods according to the user's fighting style. For more information, you can see the following review.
1. Shigan “Orange”
The first variation is Shigan "Oren" which was used by Rob Lucci to attack Luffy in Enies Lobby. The attack is similar to normal Shigan, but the user casts it many times in quick succession.
2. Tobu Shigan
Tobu Shigan is issued by shooting Shigan like a sharp air bullet and can cut the opponent. There are two characters who master this variation, namely Stussy, Rob Lucci, and Who's Who.
Lucci even developed several special techniques from Tobu Shigan, such as Bachi, Mitsubachi, and Hibachi in the form of fireballs.
3. Bigan
Bigan is a unique version of Shigan that was specially developed by Kaku when he entered his Hybrid form. If Shigan used to use his fingers, Bigan relied on Kaku's square nose.
4. Shigan "Madara"
Shigan "Madara" has a way of working similar to Shigan "Oren". The difference is, Shigan "Oren" relies on one index finger, while Shigan "Madara" uses two index fingers at once. So far, this technique has only been showed by Rob Lucci and Who's Who.
5. Juushigan
Jabra also developed a unique variation of Shigan called Juushigan. He uses his ten fingers to deal powerful damage to the enemy. Additionally, that technique is used by Jabra when he entered the Hybrid form.
6. Shigan Cue
Unlike Jabra and Kaku, Kumadori has a unique technique called Shigan Cue. When issuing the technique, he relies on the blunt tip of his staff to attack the enemy.
7. Shishi Shigan
Kumadori still has one more variation of Shigan called Shishi Shigan. First of all, he would manipulate his hair and shape it into hands. Then, he would raise his finger-shaped hairs to stab the opponent's body aggressively.
8. Jugon
Jugon is a version of Shigan developed by Fukurou. The technique took the form of a strong fist that flew as fast as Shigan so that the effect of the fist was even more fatal. He could even combine it with Soru to create even more powerful variations.
9. Shinaru Shigan “Whip”
Like her friends in CP9, Kalifa also has a unique Shigan technique called Shinaru Shigan “Whip”. Upon casting the technique, Kalifa's hand moved so flexible like a whip and shot out at high speed.
10. Hagan
Before becoming a member of the Beast Pirates, Who's Who was a member of CP9. He also mastered various Rokushiki techniques, especially Shigan. Uniquely, he has two interesting variations of Shigan, named Hagan and Gagan.
Hagan was kicked out by Who's Who relying on the dagger he usually carries with him. He then issued knife thrusts in succession until his attacks produced a sort of sharp bullet from the air.
11. Gagan
Unlike Hagan, Gagan is a combination technique of Tobu Shigan with Who's Who's devil fruit. When in hybrid form, Who's Who will issue a barrage of attacks in the form of very sharp canines.
12. Shugan
Shugan is Rob Lucci's new move that he released after he mastered his devil fruit awakening. When casting the technique, Lucci used his five fingers and quickly stabbed the enemy's body. He used the technique to attack Sentomaru on Egghead Island.