Bloons Tower Defense 4 Expansion contains 4 brand new crazy fun tracks for you to try out. Mesmerise yourself on the Sandy Spiral Track, get lost in the Subterrainian Sewers, explore the secrets of the Monkey Temple, or challenge your wits on the Triangle of Insanity! This expansion also includes a new game mode called Deflation mode. You start Deflation mode with 50,000 money but you never get any more.