These runes were added into Diablo I through the Hellfire expansion set. They were single use items, similar to a scroll, but were placed on the ground like a trap.
“Effect: Casts Lightning Wall, Requirement: 13 Magic, Quality level: 3, Cost: 200 goldRune of Lightning
“Effect: Casts Nova, Requirement: 42 Magic, Quality level: 7, Cost: 500 goldGreater Rune of Lightning
“Effect: Casts a fireball/Creates a one-square fire flame., Requirement: None., Quality level: 1...Rune of Fire