While it fails to see what the Painter saw, the ending reveals that the Goo Balls that escaped back at the end of Chapter 1 have managed to reach a far-off planet and repopulate it with nothing but Goo Balls, meaning that they are no longer endangered of being used or going extinct. The last level reveals that the Goo Balls have gone completely extinct, and you use some balloon-like fish to raise the telescope beyond the layer of smog. Later, the Epilogue reveals that all Goo Balls, except the 'scientifically pure' ones, have been sucked away to the 'Tower of Goo Memorial Park and Recreation Center'. Bittersweet Ending: The World Of Goo Corporation is destroyed and Product Z is shut down, but the world is left in ruins.The colour scheme becomes predominantly green, and the new Goo species has a cubic shape, both of which are meant to evoke the look of the Cyberspace. Art Shift: In Chapter 4, Product Z turns the entire world three-dimensional.Alice and Bob: Used in a Chapter 4 level called 'Alice and Bob and the Third Party', where you intercept information-goo transmitted from cosmicGrrrl! to LaconicCrusadr13.The game hints either way, for instance, it's hard to tell whether their politeness is genuine or threatening. Ambiguously Evil: It is never made clear whether MOM is a misguided, but well-intentioned artificial intelligence, or a crazed spambot who only cares about getting more users.Alertness Blink: Newly-awakened goo balls produce a peculiar sound and a visible '!' above their eyes as they become active.Advanced Tech 2000: The Freedom Scraper 3000 in 'Welcoming Unit'.

In other cases it can be used to balance a structure much faster than using the whistle.

Advanced Movement Technique: Thwacking, the act of quickly throwing a goo ball at a structure, can often be used in place of actually building a structure.

20% More Awesome: When you unlock Tower of Goo Memorial Park and Recreation Center, its description reads that it's 'Now 20% more infinite in all directions'.

World of goo big fish