Slitherlink: Around the W0rld

Question

Rules of Slitherlink:

Connect adjacent dots with vertical or horizontal lines to make a single loop.
The numbers indicate how many lines surround it, while empty cells may be surrounded by any number of lines.
The loop never crosses itself and never branches off.

Link to Penpa version (let me know if there's a mistake, I transcribed this manually) — HTM, Apr 01 '21 at 04:52
Haha! I had a feeling the [tag:seasonal] tag was going to prove appropriate here! :) — Stiv, Apr 01 '21 at 06:03
An alternative (and perhaps superior?) version of the joke involves a rot13(yratgu fvk ybbc fheebhaqvat gjb guerr pyhrf) :) — happystar, Apr 01 '21 at 09:07
@happystar yes!! I once found it published by someone and I was dumbfounded :)) — athin, Apr 01 '21 at 09:19
Daft Punk would love this puzzle. https://youtube.com/watch?v=LKYPYj2XX80 — Stilez, Apr 02 '21 at 03:29

HTM · Accepted Answer · 2021-04-01T06:26:42.183

The solution is (drumroll please...)

Yep, that's it. All those clues for just a measly square. (I guess that's why this puzzle's tagged humor!)

Explanation:

We start by

marking the edges where the loop cannot pass through due to the 0 clues:

Next,

we progressively mark off edges coming off of dots where the other three edges (two for a border dot, one for a corner dot) coming off of them are marked as unusable. We continue to do this until we reach a state like this - note the square at R10C16:

And here's the coup de grâce:

It appears that we're able to make a connected loop spanning the entirety of the grid, but actually we can't (!) due to the edge marked with the star below not being usable: Thus, we are forced to use the square mentioned earlier for our loop, giving us our final solution.

Nicely done and well explained! XD – athin Apr 01 '21 at 08:35 — athin, Apr 01 '21 at 08:35
@athin Thanks, this is a really nice construction! – HTM Apr 01 '21 at 08:37 — HTM, Apr 01 '21 at 08:37

Slitherlink: Around the W0rld

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