This is a three-dimensional mixed-breed puzzle. The five squares depict the five layers of a $5\times5\times5$ cube. The goal is to solve the odd-numbered layers as yajilin and even-numbered layers as masyu.
- Shade some cells on odd-numbered layers. The numbered cells show how many shaded cells are in the direction of the arrow.
- Shaded cells cannot be adjacent to another shaded cell, but they can touch the numbered cells.
- Unshaded cells on each yajilin layer are all connected in 2D (i.e. each layer is treated separately).
- Make a single loop in 3D space which goes through every unshaded cell on odd-numbered layers, and every circle on even-numbered layers.
- A line passing through a white circle must continue straight through its cell and make a turn in the directly following or preceding cell (or both).
- A line passing through a black circle must make a turn inside that cell and continue straight for at least one cell on both sides.
Note: Feel free to use any notation you feel the most comfortable with, as long as it's properly explained. My way is to use diagonal lines to show movement between layers.