|Affiliations|| Forever Knights|
Negative Ten (formerly)
|Powers and Abilities|
|Abilities|| Martial Arts|
|Equipment|| Specialized Armor|
|Alias|| Forever Knight Ninja|
Ninja Boy (Four Arms)
|Voice Actor||Kevin Michael Richardson|
|First Appearance||Ben 10 vs. the Negative 10: Part 1|
The Forever Ninja is also seen in An American Benwolf in London, but later defeats itself by holding the Proto-Tool backwards and shooting an energy blast at itself, but was salvaged by a mutated Chadwick.
Powers and Abilities
The Forever Ninja has enhanced strength, speed, agility, stealth and battle tactics.
The Forever Ninja has a limited self-repair system to repair minor damage.
The Forever Ninja has an assortment of weapons, including energy swords and various shurikens and throwing projectiles.
Loud noises such as sonic booms or the large bell of the Big Ben Clock Tower can disrupt the Forever Ninja's system.
If the Forever Ninja takes enough damage, it will shut down.
Its Artificial Intelligence is not as advanced as some of the other robots seen in the series; While holding the Proto-Tool, the Forever Ninja accidentally shot itself in the chest due to holding it backwards.
Ben 10: Omniverse
- Some Forever Ninjas appear in Ben 10: Alien Force (Video Game) and Ben 10 Ultimate Alien: Cosmic Destruction in Tokyo.
- Despite being called the "Red Knight", it's color is more of a brownish-maroon, until Ben 10: Omniverse, where it is crimson red.
- The Forever Ninja has a resemblance to Snake Eyes from G.I. Joe.
- The Forever Ninja spoke in Ben 10: Alien Force (Video Game), but never has in the actual show.