Great Balls of Fire
From the Super Mario Wiki, the Mario encyclopedia
Located in the city of Mythis, the Great Balls of Fire are guarded by the hero Hercufleas, who keeps them in his acropolis home. The Great Balls of Fire are evidently more powerful than regular fireballs, as they were shown to explode violently upon contact with an object, creating an explosion powerful enough to destroy a stone wall and pillars.
The Great Balls of Fire can also be controlled mentally by whoever is in possession of them, as King Koopa was shown to make several of the Great Balls of Fire chase Mario and Luigi by simply concentrating and making gestures with his hands. The Great Balls of Fire are also finite, meaning that they will eventually be extinguished if used too much. If the Great Balls do run out, they can seemingly be ignited once more by simply placing fire in the urn the Great Balls of Fire are kept in.