A bug in poker

Poker

Poker is a family of card games that share betting rules and usually hand rankings. Poker games differ in how the cards are dealt, how hands may be formed, whether the high or low hand wins the pot in a showdown , limits on bet sizes, and how many rounds of betting are allowed.In most modern poker...

 is a limited form of wild card

Wild card (poker)

Card games, particularly poker games, may contain one or more cards designated as wild. These may be jokers, or they may be normal ranked and suited cards pressed into wild card duty . In most cases, the wild card or cards must be agreed upon by all players before the cards are dealt and play...

. One or both jokers

Joker (playing card)

Joker is a special type of playing card found in most modern decks, or else a type of tile in some Mahjong game sets.-Name:It is believed that the term "Joker" comes from a mispronunciation of Jucker, the German/Alsatian name for the game Euchre. The card was originally introduced in about 1860 for...

 are often added to the deck and played as bugs.

In draw poker

Draw poker

Draw poker is any poker variant in which each player is dealt a complete hand before the first betting round, and then develops the hand for later rounds by replacing, or "drawing", cards....

 played for high and pai gow poker

Pai gow poker

Pai Gow poker is an Americanized version of Pai Gow . The games of Pai Gow poker and Super Pan-9 were created by Sam Torosian and Fred Wolf.The game is played with a standard 52-card deck, plus a single joker...

, the bug is considered to be an ace, unless it can be used as a missing card to complete a straight or a flush, in which case it becomes the highest card which can complete the hand.

• K-K-Joker-5-2 is a pair of kings with an ace kicker
  Kicker (poker)
  A kicker, also called a side card, is a card in a poker hand that does not itself take part in determining the rank of the hand, but that may be used to break ties between hands of the same rank. For example, the hand Q-Q-10-5-2 is ranked as a pair of queens. The 10, 5, and 2 are kickers...
  
  .
• A-A-Joker-9-4 is three aces.
• A♥ J♥ 8♥ 3♥ Joker is a flush, ace-king high, the bug becoming the K♥, even if another player holds the "real" K♥. (But see double-ace flush for a variant rule.)
• 7-6-5-4-Joker is an eight-high straight, the bug becoming an eight rather than a three since both complete the straight but the eight is higher.
• J♣ 10♣ 8♣ 7♣ Joker is a straight flush, jack high, the bug becoming the 9♣.

In California lowball

Lowball (poker)

Some forms of poker, often called lowball, sometimes called low poker, reward poor poker hands . There are four common variations on this idea, differing in whether aces are treated as high cards or low cards, and whether or not straights and flushes are used. The methods are:* Ace-to-five low:...

, the bug is the lowest unpaired card in a hand. For example in 8-6-4-3 plus the bug, the bug becomes an ace; in A-2-3-5 plus the bug, the bug becomes a four.

Holding the bug greatly increases the power of certain drawing hands. For example, playing for high, a natural four-straight such as Q-J-10-9 drawing one has nine outs

Out (poker)

In a poker game with more than one betting round, an out is any unseen card that, if drawn, will improve a player's hand to one that is likely to win. Knowing the number of outs a player has is an important part of poker strategy. For example in draw poker, a hand with four diamonds has nine outs...

to complete the hand, any king or eight or the bug. By contrast a four-straight including the bug can have as many as sixteen outs to complete the straight - Q-J-10-Joker can catch any ace, king, nine, or eight.