A Transport Bubble is a magically created form of vehicle utilised by the heroes throughout the series.
The bubbles are large and transparent, usually with a large wooden bench placed inside. At least four individuals can travel inside. Who can enter the bubble depends on it's owner however, being powered by their imagination. The bubbles are usually created via the Dream Maker's machinery, though methods of creation are shown, perhaps most grimly from turning animals into them.
No known weakness is described for the bubbles, them seemingly impenetrable to anyone who tries to break and trespass into them, this makes them very durable for long travels, even into outer space. They can however be easily immobilised, which has the setback of trapping it's owners in a readily made cage should an enemy capture it.