Helping Other Players Complete Their Full Sets is Good karma
Since a Deal Breaker can only be used to steal full sets sometimes it’s good strategy to “help” your opponent complete a full set. One way to “help” your opponent is to entice them into completing that set. For example, if your opponent has two dark green property cards on the table (none are dual color wild property cards) and you have one in your hand (as well as a Deal Breaker), laying it down may be enough to entice them to steal it to complete their own full green set, you can then use your Deal Breaker on your next turn to steal that full set...