How the world works
Red balls
Red balls are made with a compound called thermite, which gives them their color and a combustive nature. At the right temperature they don't melt like other balls. They explode.
The same compound is used to repair damaged seals, closing wounds with precision.
Red balls learn they're combustive as kids. Ace and Captain are both red. When Ace tells Scout's father "There's a reason I am red," he means it.
Appears in
The Shape Beneath the Silence · Season 1, Adventure 1