Cracking the Joker Power Code in Rummy. When used properly, jokers and wild cards can significantly change the outcome of a game in rummy. These cards are immensely valuable assets in your rummy bonus listpossession because they can be used to form melds in place of any other card. But with power comes responsibility, and the secret to maximizing their potential is knowing when to use them. Using Jokes Strategically. For example, using a joker can help you finish a run that is almost complete but is missing one card, which could allow you to go out sooner than your opponents.