|Ding Xiao Yu|
|Role||Main character, support character, special guest|
|Battle Level||8500 (later 10000+)|
|Special abilities|| Explosive Fists|
|Home World||The Gold Dimension|
|Alternate counterpart(s)||Jiu Wu (The Iron Dimension)|
|First Appearance||Episode 1, KO One|
|Portrayed by||Aaron Yan (炎亞綸)|
He is the 4th ranked fighter on the KO Ranking Record, his fighting count being eight-thousand five-hundred, which later advances to over ten thousand. He is prone to giving others cold looks if they are not willing to leave him alone.
Xiao Yu has dislike to violence, but if anyone hits his head, he will definitely fight back. This is a trait that he developed from a traumatizing childhood.
Unlike everybody else, he lives in a tent instead of a real home and has no family of his own.
Xiao Yu is more likely to be found spending time in the music room because he likes to play the piano. His music is so touching that anyone who hears it can be reminded of what it's like to love others.
At the beginning of the series, he appeared to be a very quiet and mysterious kid, but after befriending Ya Se and Da Dong, he begins to show a cheerful character and even starts to smile. Xiao Yu was transferred to Ba Le High School from Kuo Nan High School.
In the middle of the series, he develops affections to Da Dong's girlfriend, An Qi.
In The X-Family (終極一家), he becomes a secondary character, only appearing when Xiu pays them a visit. Picking up from where KO One left off, Xiao Yu remains powerless throughout the series and is waiting for Xiu to find his alternate counterpart in the Iron Dimension restore his powers.
Sometime before K.O.3an Guo (終極三國), Xiao Yu and his friends restored their powers, much to their delight. During the pilot episode, they have Xiu take them to the Silver Dimension to try dimensional travels. While trying his cellphone's camera, Da Dong accidentally drops a coin that accidentally causes a gigantic rock to fall on Xiu's doppelganger, Liu Bei. They then take Liu Bei back to their world for medical treatment while Xiu assumes his identity until he recovers from his injuries.
- "King of Endurance" (耐打王 / Nai Da Wang)
- "Life-taking Xiao Yu" (要命的小雨 / Yaoming de Xiao Yu)
- Wang Da Dong (汪大東) and Wang Ya Se (王亞瑟)
Xiao Yu became best friends with Ya Se and Da Dong after he saved them from a gang of gangsters. After that night, Da Dong proclaimed him as one of his best friends because he saved them without looking for profit. It was via this friendship that made he begin to smile. When he fell in love with Da Dong's girlfriend, An Qi, he chose to rather pay the price than putting up a fight for her heart. After they solved their problem, they returned to their relationship as best friends.
- The Iron Dimension
- Xiu (脩)
Xiao Yu and Xiu become good friends after they spend time with each other for training. After Xiao Yu lost his powers, Xiu promises to help him, Da Dong and Ya Se find their alternate counterparts in hopes to restore their powers via them. Even after Xiao Yu's powers were restored, the two of them remain as really good friends.
- Huang An Qi (黃安琪)
Xiao Yu carries a cellphone with him, but never gives his number to anyone - including Da Dong and Ya Se. But when he falls in love with Da Dong's girlfriend, An Qi, he gives it to her and tells her to call him whenever she's in need of help. Da Dong eventually finds out that he is in love with An Qi and the three of them become odd against each other, and prefer to rather not talk about their relationship. Their relationship ends with An Qi deciding to return to America. After this, Da Dong and Xiao Yu solve their problem and become friends again. At one point, Xiao Yu declares that An Qi belongs with Da Dong and not him. For more information, go to Ding Xiao Yu and Huang An Qi.
Powers EditLike many other characters, he displays the abilities of super-speeding and telepathic communication.
Unlike Da Dong and Ya Se, who use weapons in action, he utilizes his powers through his fists: Xiao Yu's left fist is said to have the power of an atom bomb, while his right fist has ten times the power of his left fist. However, if he uses his right hand, he will use up all of his energy.
Xiao Yu can also produce healing factor to speed up the healing process of his injuries, and produce a protective force field around those behind him.
In the series finale of KO One, Xiao Yu borrows Lei Ke Si's weapon, Ares' Hand, to increase the power of his right hand to aid him in battle against Hei Long. As soon as he puts on the metal glove, his power becomes tainted with demonic energy and instantly makes him more powerful. With it, he is able to shoot energy beams from his right hand without using up his power. After their combat against Hei Long, he gives it away, seemingly giving it back to Lei Ke Si.
Alternate Counterpart Edit
Jiu Wu (灸舞)Edit
- Main article: Jiu Wu
|Top 10 KO|
| KO 1: Tian Hong Guang | KO 2: Lei Ke Si | KO 3: Wang Da Dong/Wang Ya Se | KO 4: Ding Xiao Yu | KO 5: Tong Da You |
KO 7: Cai Yun Han | KO 9: Cai Yi Ling
| KO 11: Da Li Jun | KO 13: Sha Jie | KO 14: Tao Zi | KO 15: Bai Linda | KO 19: Zhong Quan |
KO 21: Tian Cai Xiao Diao Shou | KO 22: Bing Qi Lin | KO 23: Na Lu Wan Zai | KO 24: Xuan Wo Ming Ren | KO 25: Bing Qi Bu
KO 26: Kua Ke Brothers | KO 27: Guai Yi Bo Shi | KO 28: Zang San Feng
|KO 135: Jin Bao San | KO 150: Elementary Student|