The phrase "goo balls" refers to small, sticky and squishy objects that are often made of a stretchy material. They are fun to play with and can be molded into different shapes. Full definition
Players will have to puzzle out four - plus worlds, with about 10 stages each, with the help of multiple types of goo balls. (thatvideogameblog.com)
Touch screen controls nullify this issue, but only at the cost of less accurate goo plucking and additional frusturation when I couldn't select small goo balls with my large fingers. (nintendocastle.com)
Once a character takes one too many goo balls to the dome and becomes «too tired» to continue that level, the only option is substitution. (gameplanet.com.au)