Allumwandlung ([ˈalʊmˌvandlʊŋ], German for "complete promotion", sometimes abbreviated AUW) is a chess problem theme where, at some stage in the solution, a pawn (or sometimes pawns) is promoted variously to a queen, rook, bishop, and knight.
A Babson task may appear if both pawns are spotted in an individual problem, corresponding one another.
[1] The diagram shows a chess problem with Allumwandlung composed by Niels Høeg and first published in 1905.
The key move (White's first move) is 1.f7, and depending on how Black defends, White promotes to either a queen, a rook, a bishop or a knight on move two.
White plays 4. c8=R and has a decisive lead (Stockfish evaluation +6.7).