A bug in poker is a limited form of wild card. One or both jokers are often added to the deck and played as bugs. The bug is played as an ace unless designating it as a different card would complete a straight, flush, or straight flush. For example, the hand K-K-Joker-5-2 is just a pair of kings (with an ace Kicker), but any four same-suit cards with a bug make a flush, and a hand such as 7-Joker-5-4-3 makes a straight.
