Played as a casual game during a break in the London 1851 tournament, this is arguably the most famous chess game ever recorded. Anderssen sacrifices a bishop, both rooks, and finally his queen — ending the game with only three minor pieces left on the board — to deliver checkmate with what remains.
By the end, Anderssen has given up more material than most games see traded in their entirety, and still forces mate. It became the defining example of the swashbuckling "Romantic era" style of 19th-century chess, prized for beauty and initiative over pure material accounting.
Historical note: chess historians have long debated whether the final few moves (20...Na6 onward) were actually played on the board or whether Kieseritzky resigned right after 20.Ke2, with the forced mating sequence simply calculated and published afterward. Either way, the combination is completely sound, and it's reproduced here exactly as it appears in essentially every published source.