Infecting Purple Cities
On the BrinkPandemic
When an Infection card hits a city that has a purple cube, add 1 purple cube as well as its own colour (unless that colour is eradicated). In an Epidemic's Infect step, a city with purple gets only its 3 own-colour cubes. Purple outbreaks work normally in Mutation. Running out of purple cubes when one is needed loses the game.
Also answers
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