Historical Rules · 18 June 2010
Rule 605.1a
Official source text from the 18 June 2010 Rules release
An activated ability without a target that could put mana into a player's mana pool when it resolves is a mana ability.
Historical Rules · 18 June 2010
Official source text from the 18 June 2010 Rules release
An activated ability without a target that could put mana into a player's mana pool when it resolves is a mana ability.