Logic Masters Deutschland e.V.

Sniglett created a fantastic puzzle called Whispers Between Worlds (definitely give it a go!) a while back, and it inspired this. We collaborated and have come up with two versions of the same puzzle. Snigletts version will be available here shortly, and will be the more difficult of the two. The previous and next puzzle in the series:
Equality Cages 113: What line is it anyway?
Equality Cages 115: Chinese philosophy

All my series:
Equality Cages
EquaLite Cages
Shifter Lines
Shifter Dots

Below the rules there's an image with some visual aid and an example solve to demonstrate the concept. At the very bottom there will be some hints hidden if you get stuck.



Rules:
The grid consists of 4 differently colored 4x4 areas. Each area is a different layer (considered to be stacked on top of each other), and together they make up a 4x4x4 cube. There are 4 groupings of digits; low (1,2,3,4), high (6,7,8,9), even (2,4,6,8), odd (1,3,7,9). Each layer is to be filled with digits from only one group, and no two layers can have the same grouping of digits. It is up to the solver to deduce which group of digits belong in which layer. Digits may not repeat in any row, column, or 2x2 box WITHIN ITS LAYER, and digits can also not appear in the same relative position in another layer. For example, the black 6 on the image means 6 could never be in any of the cells with the smaller-sized digits.

Equality cages: Cages must have an equal number of low (1,2,3,4) and high (6,7,8,9) digits AND an equal number of even (2,4,6,8) and odd (1,3,7,9) digits. Digits may not repeat in a cage. The letters are for identification purposes only.

Between lines (top left layer): Cells along lines between two filled circles must have values between those in the circles. Digits may repeat on between lines.

Dutch Whispers (top right layer): Adjacent digits along each Dutch Whisper line must have a difference of at least 4. Digits may repeat on the line.

Thermometers (bottom left layer): Digits along each thermometer must increase starting from the bulb end.

Renban (bottom right layer): Digits along each renban line must be a set of consecutive digits in any order, and must not repeat.



There is a setting (under Gameplay) called "Conflict Checker", and I'd recommend you set that to "Off", as well as "Check Pencilmarks" which I'd also recommend setting to "Off".

Solve here:
Sudokupad

Video featuring the puzzle:
Sudoku Sleuth

Help:
In order to look at the hints below, highlight the text (which is written in white).

Hint 1: Isn't it oddly specific which digits can go on the layer with the Dutch Whispers?
Hint 2: What do you know about the C-cage and the long thermometer?
Hint 3: The cages on the short thermometer are interesting.
Hint 4: There's a lot of work to be done in the layer with the renban lines.
Hint 5: Explore the cages.
Hint 6: Have you considered the between lines?
Hint 7: If you're feeling disjointed at this point it might be wise to think 3D.