also known as Bluff
2–6 players, a standard 52-card deck. This is a single, unscored round — emptying your hand makes you safe, but play keeps going. The very last player still holding cards loses.
The entire deck is dealt out to all players, so hands may be uneven by a card or two.
On your turn, you either add to the pile that's currently open (still claiming its already-established rank) or, if nothing's open, lead a fresh pile claiming any rank you like — up to 4 cards per play. The cards you actually play don't have to match the claim! Lying is completely legal.
Instead of adding, your turn can be a challenge on whoever added to the pile most recently. The challenged contribution is revealed: if it was a lie, the bluffer picks up the whole pile and the challenger takes control, leading a fresh claim next. If it was true, the challenger picks up the whole pile instead — the cost of guessing wrong — but control returns to the player who was right, who leads the next claim.
A pile that survives a full lap of the table back to its own starter, unchallenged, is theirs to decide: pass to retire it for good — nobody ever picks it back up — and immediately lead a fresh claim, or add more cards to keep it going. Anyone else passing just defers their turn; the pile stays open.
Emptying your hand doesn't end the round — it just makes you safe; you're skipped for the rest of the game. Play keeps going until only one player still has cards. That player is the loser — everyone else wins.