An incredibly easy strategy used by terran players in the game Starcraft 2:Wings of Liberty. The bioball is unstoppable when it reaches critical mass. It is only beaten early on through sheer skill or a bigger bioball.

It is considered a tactic used by noobs and is sometimes considered to be overpowered. The bioball takes the least amount of skill possible for an RTS game to use.
I got bioballs of steel.

That f***ing bioball is overpowered.

Bioball A-click to victory.
by l337 haxorz August 23, 2010
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