Rune of Flame

The Rune of Flame is a runic spell that appears in Ultima Underworld II.

Description
The Rune of Flame places a magical ward at a fixed location, which takes the form of a floating Flam character. After it has been cast, any creature which touches it will be subjected to a torrent of magical fire as the rune dispels itself. This spell, and others like it, may be unwoven through use of the Dispel Rune incantation. 

Trivia

 * It is possible to bypass the Rune of Flame by hurling an object into it, although the item will be damaged and possibly destroyed in the process. Pieces of refuse or gold coins (which have no mechanical damage ratings) are useful for such actions.