Big O rules

• PLO8 with five hole cards.
• Your hand still uses exactly two hole cards and three board cards, and the pot is split between high and low.

Base: PLO8

Differences from PLO8:

• Five hole cards. There are 10 ways to pick two of them (6 with four cards)
• You still use exactly two hole cards + three board cards
• More combinations make everyone’s high and low hands stronger

Pot-Limit, Hi-Lo (8-or-better) and blinds are the same as PLO8.

Example. Board K♥ 9♥ 6♥ 3♦ 2♣, pot 100.

• X: A♥ 4♥ 5♠ 7♣ Q♦
  • High: A♥ 4♥ + K♥ 9♥ 6♥, an ace-high flush
  • Low: A♥ 4♥ + 6 3 2 = 6-4-3-2-A
  • The same two of the five cards (A♥ 4♥) make both
• Y: K♠ K♦ 9♠ 8♣ Q♣
  • High: K♠ K♦ + K♥ 9♥ 6♥, three kings
  • The only hole card of 8 or lower is 8♣, so no low
• X wins both high and low and takes the whole pot of 100

Sources

• Poker TDA Rules (2024 version: Rules 47 and 48; short all-in raises and the number of raises)
• Robert Ciaffone, “Robert’s Rules of Poker” (the half-bet rule in limit)
• PokerNews and Wikipedia rules pages for each game