#23: Clone Loop

 made on 12/15/20

https://swaroopg92.github.io/penpa-edit/?m=solve&p=nZJPa8MwDMXv+RTBZw9q+U+Gb2N/TqWHtWOMEMYOgYYGsnXJJaH97H3W5K3nYfT4ISQ92cn31/RxbHXAsbd6pQ0OhcBhnONYydl1Y9/GctMdhr676btDW66H4VPfTeN+OMZyP41jjqKWrqaolVFaEcKo5jxvz7VS2jTFMj/HZX6PdXPS88sfbuMC3bAa1jfWJ1Zi3aFUz5b1gXXF6lnXXPMYF2U8aRNIRYJ7SGx/2IG95B0u7XKN1aaSGouanE9scx41Ls8Be2Gf2Anj6YJwmpk55b0X9sgLB3AlTMlLfA2Y8m74JFWQXnAQdmB/xa4SxszsldhJjQFT9sI+12xlT8ufXnrTzsKUemUOwYuSFx77lZ/8ntVBT0VRp3v8HvT9l/ELNRc=

Rules:

- Draw a loop between cells.

- Regions with the same shape are passed through by the loop in the same cells of that shape, rotations and reflections allowed.

- Regions cannot be entirely filled by the line or entirely empty.

Despite being the first one I made, it is tough. If you need solving tips, consider what the third rule implies about dominoes and whether the corner of the L tetromino can be shaded.

(Highlight text to reveal spoilers.)