Like its predecessors 6 nimmt! and 11 nimmt!, Wolfgang Kramer's Bullenparty has players lay out numbered cards, then collect bullheads – but the details of game play require you to point your horns in new directions.
Bullenparty uses two decks of cards: one numbered 1-100 (with each card bearing 1-7 bullheads) and the other with ten Bull cards, bearing 4-7 bullheads. At the start of the game, each player receives five number cards at random along with a zero card.
At the start of each round, lay out one row of number cards for each player, with two cards in each row. Each turn, all players secretly choose a card in their hand, then reveal them simultaneously. Whoever played a number card chooses all of the cards in one row and adds them to his hand, discarding the card used for bidding. Whoever played a zero card adds a card from the top of the deck to a remaining row, then reclaims the zero card. All players who played zero cards then repeat this process. If a row reaches five cards in length, add the top card from the Bull deck to this row; if all rows end in Bull cards, then players must play number cards.
Whenever a player picks up a row, they must then immediately reduce their hand to five number cards (not counting their zero card, which they keep throughout), playing any excess cards in hand onto one or more stacks in front of them, with cards being played in ascending order. Bull cards are placed separately.
After the last row has been picked up, the round ends. Players then create new rows and play another round. When the deck runs out, shuffle the discards to finish the round, after which the game ends. Players then score positive points for Bull cards and for the bullheads in the pile with the most bullheads; all other bullheads are negative points. The player with the highest total score wins.