GameplayUse the mouse or arrow keys to control the grey goo. Eat everything that is smaller than you. The more you eat the bigger you get. You must get to the required size in order to beat the level.
Current SizeThe current size display shows you how big your grey goo is. Eat more stuff to grow bigger.
Required SizeYou must reach this size to beat the level.
Just EatenThis displays the last item that you have eaten.
Helper ArrowThe arrow and cursor tell you what you can eat. The arrow will point to the largest item in close proximity that you can eat. You should eat this item and everything smaller.
Time LimitYou must grow to the required size before time runs out (note that there is no time limit in casual and endurance modes).