The Third Dimension is a Special Extreme Track that can be only accessible by crafting and using an Omega Gem. You will leave your game (nothing will be saved, so it is adviced to save before crafting it!) and enter this track. It has 120 rounds and is in Medium Difficulty. The boss is the real Omega Bloon. Unlike other Extreme Tracks, you don't have to pay to enter. You can't use Special Agents in this track. You can't play Freeplay Mode in this track.