A Small missile platform requires a mind rune and an elemental rune (air, water, earth or fire) to shoot a player over the gap by briefly turning them into the respective strike spell. They always appear in pairs.
The type of elemental rune used depend on the amount the player has in their inventory. The most abundant rune type would always be used. If more than one rune type is equally abundant, the lower level one would be used. For example, water runes would be used over fire runes.
It appears that runes are only consumed when going one of the two directions available from a pair of the platforms. This is a measure to prevent players from getting stuck on dead end floating islands.
