It's very simple actually.
We divide up in to teams of 3 or more (usually with 2-4 people on a team). We go on degpaint online and the host creates a blank canvas to start. Each member of a team is given a different size brush (small, med, large, or extra small if 4 people), no repeats for each team and then that team is given a color (blue, red, green, purple, etc...). The first team to cover over 40% of the canvas with their color wins, this is calculated by degpaint online of course. Obviously you can cover over the other teams colors with your own team color.
It's quite difficult to do though as with 3+ teams covering 50% can be difficult, plus getting everyone online at one time is a pain. It is usually won after someone goes afk or quits.
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