Yellow Radio, as the Yellow King, is a very powerful and commanding figure. He is shown to be rather manipulative and cruel, being suspected of stealing the Armor of Catastrophe — which led to the creation of the Fifth Chrome Disaster — all so that he could exploit the rules of the Mutual Nonaggression Treaty to kill the Red King.
Yellow Radio is not completely indifferent to the interests and wellbeing of others, however. For example, in Volume 25, he teleported all of the Kings (excluding White Cosmos) out of the reach of the Apocalypse God Tezcatlipoca, saving them from Infinite Enemy Kill. He could have easily saved only himself, allowing the others to die, but he instead chose the more difficult route to save the other Kings as well.
As an interesting alternate point of view, Aqua Current describes Yellow Radio as being only a "ham who wants attention". This implies that most of his actions are done in order to garner the attention of others.
In the early days of Brain Burst, Yellow Radio, alongside the other Kings of Pure Color, attained level nine. As the Yellow King, known as the "Radioactive Disturber", he was present for many of the legendary incidents in Brain Burst's history.
Yellow Radio allied with the other Kings in the decision to create the Mutual Nonaggression Treaty in order to avoid the cruel Level Nine Sudden Death rule. This treaty separated their territories and prohibited fighting amongst themselves (which was necessary to reach Level 10).
He also took part in the past Chrome Disaster subjugation missions.
Finally, Radio was present when Black Lotus called for the dissolution of the treaty, as well as when she beheaded the Red King, Red Rider. Unlike the other bystanders, however, Radio recorded the entire incident.
He has the appearance of a jester, with two large yellow ball-tipped horns on his head.
Crimson Storm Princess Arc
Yellow Radio appears along with his legion in the neutral field to kill the Red King, Scarlet Rain who is currently trying to stop Chrome Disaster with the help of Nega Nebulus. He openly states that Chrome Disaster has killed several members of his legion and as the rules state that if that legion is unable to kill the traitor, someone from the legion must be sacrificed instead. However, Scarlet Rain and Silver Crow suspect that Yellow Radio was behind the whole incident of the fifth Chrome Disaster to eliminate Rain to get to Level 10. As Yellow Radio chooses to kill Scarlet Rain, Silver Crow and the others decide to help her. Before the fight begins, Yellow Radio is able to incapacitate Black Lotus by simply making her feel guilty on the crime that she committed which was the death of Red Rider, the first Red King.
Scarlet Rain and the Nega Nebulus attempt to run as the Yellow Legion starts to open fire on them. Silver Crow activated his wings, but Yellow Radio used «Silly-Go Round» on him to confuse him. When Cyan Pile was destroyed, Rain activated her Immobile Fortress. Yellow Radio encouraged his legion not to be afraid, ordering them to tear the fortress apart. Despite the Red King's overwhelming firepower and assistance from Silver Crow, they were just two against a whole army, which slowly wore them down.
During their fight, Black Lotus was able to recompose herself and defeated the Burst Linkers that were attacking Scarlet Rain. As she came to face Yellow Radio, he asked if she doesn't feel any guilt for beheading Red Rider. He jokingly wonders where their friend is now and what he's up to, whether he remembers the Accelerated World or not. He admits if he were in her shoes, he would never do something like that again nor forget. Black Lotus confessed that while she does feel guilt, she won't feel any from fighting him and fights one on one with Yellow Radio. With the two of them fighting on equal power, they each await for their special moves to recharge. As the both of them prepare to use their moves, they are interrupted by the appearance of Chrome Disaster who has pierced his weapon into Yellow Radio's abdomen. Initially being shocked, Yellow Radio decides to retreat. After Chrome Disaster is destroyed, Yellow Radio avoids implication in its creation.
White Legion Arc
When the Legions were attacked by the Apocalypse God Tezcatlipoca under the command of the White King White Cosmos, Yellow Radio teleported the other Kings out of the Apocalypse God's reach, thus saving them from Infinite Enemy Kill.
Yellow Radio's appearance is heavily based on that of a clown or a jester. His attire consists of a yellow clown suit with two horns. He also wears a white mask with a pink mark on the left eye. While he is a yellow avatar, focused on indirect attacks such as illusions and disorientation, his physical attacks should not be underestimated either. He was able to hold his own in close combat against Black Lotus.
- Unnamed baton – His baton becomes stronger the more times it is spun around. It can become strong enough to withstand Black Lotus' blades.
- Equilibrium – It is unknown what this ability does, but it likely allows him to maintain his balance.
- Acrobatics – It is unknown what this ability does.
- Futile Fortune Wheel – One of Yellow Radio's special moves. Its function currently unknown as he was interrupted by Chrome Disaster before he could use it.
- Deceit Firecracker – Allows Yellow Radio short-ranged teleportation.
- Silly-Go Round – Creates an illusion of a merry-go round at a target, making said target assume that the world is spinning.
- Judgement Blow – An ability given to all Legion Masters that allows them to instantly uninstall Brain Burst from one of their legion members.
He also possesses a powerful Incarnate Ability that allows him to teleport, making him the only duel avatar in the history of Brain Burst with the possession of true teleportation.
- Yellow Radio is the only duel avatar in the history of Brain Burst with the possession of true teleportation.
- Yellow Radio's Japanese voice actor, Akira Ishida, also voices the Sword Art Online character Gabriel Miller, also known as Subtilizer in GGO and Vector in Project Alicization, who is the main antagonist of Sword Art Online Alicization: War of the Underworld, as well as the hidden antagonist of Sword Art Online: Fatal Bullet's first three DLC expansions.