Logic Masters Deutschland e.V.

Link to puzzle: https://tinypuz.com/25w4asxp

Welcome to London Underground!

Well, at least a cut-out of about Paddington (r1c1) to Russell Square (r1c9) and Gloucester Road (r8c2) to Temple (r8c9). (Cf. https://www.tubemaplondon.org)

Normal Sudoku rules apply.

Meaning of the line colours:

Orange: Circle Line (r1c2 to r1c9) - Dutch whisper: neighbouring cells differ by at least 4.

Yellow: Circle Line (r1c2 to r3c1 and r7c1 to r8c4 and r8c7-9) - 3 nabner: on each no cells are adjacent to any other on this nabner.

Green: District Line (r3c1 to r6c1 and r8c4-7) - 2 German whispers: neighbouring cells differ by at least 5.

Red: Central Line (r5c1 to r5c9) - entropic: of three neighbouring cells one must be low (1,2,3), one middle (4,5,6) and one high (7,8,9).

Grey: Jubilee Line (r1c3 to r9c6) - sum 10: the digits along that line can be divided into non-overlapping groups of neighbouring cells, each of which sum to 10.

Turquoise: Victoria Line (r1c8 to r9c4) - region sum: digits must have the same sum in each 3x3 box entered by the line.

Blue: Piccadilly Line (r1c9 to r8c1) - antiregion sum: digits must NOT have the same sum in any 3x3 box entered by the line.

Black: Northern Line (r7c1-9) - renban: adjacent digits in any order.

Brown: Bakerloo Line (r1c3 to r9c8) - the digits that occur only once on that line sum to the highest digit on that line.

Oh, and never mind the gap at High Street Kensington (r6/7c1 sum to 10) - part of the puzzle, no real break in the Underground lines.

(To be honest, you will only need Brown OR Blue to solve the puzzle.)