When starting a new game in Bloons TD 4 Expansion, on the "Set Game Mode" screen after selecting a track, the player can select a Specialty. There are 7 Specialties to choose from and each one of them lowers the cost of certain things by 20%, and raises the cost of everything else by 10%. To select a specialty, click its check box. If the player usually only uses a few types of tower, it could be a great money saving technique.
Here is a list of all the Specialties, as well as what each of them affects:
All towers and upgrades cost the normal amount.
Pass Track 1, The Beach, on Easy or harder to unlock.
Pass Track 2, Sewer, on Medium or harder to unlock.
Pass Track 3, Monkey Temple, on Medium Difficulty or harder to unlock.
Pass Track 1, The Beach, on Hard to unlock.
Pass Track 2, Sewer, on Hard to unlock. (* This is what it says in game, but it is supposed to be Track 2)
Pass Track 4, Triangle of Insanity, on Medium or harder to unlock.
New Towers (new)Edit
Pass Track 3, Monkey Temple, on Hard to unlock.