How to solve Nikoli's Extra Hard Akari puzzles

Simon explains how to solve this incredible puzzle from 14 October 2017.

[@antonyduhamel1166]

I found this channel well into its prime. It's interesting to cycle back to these old videos and see the stark contrast.

[@racoon_in_ankhmorpork]

I never thought that watching a man solve puzzles for hours on end could be so entertaining. Thanks for making me discover the world of these magnificent looking puzzles, I shall endeavor to start solving them myself :) After binging this channel’s content, I came across this old video, and I must say that, while I personally prefer sudoku, these akari puzzles look super fun too, can’t wait to try some!

[@keeegz95]

so it's kinda like minesweeper? Just found your channel recently through recomended (praise the youtube algorithm) it's getting me back into sudoku (especially killer sudoku) and even though im pretty bad, it's a lot of fun! Awesome work, i hope you guys get even bigger because more people need to see this :)

[@ardemus]

There must be rules that you didn't mention... OK, it's just that you can't place a light in the beam from another light.

[@user-tr7uo3vh7v]

beautiful puzzle

[@tremkl]

Never seen that puzzle type before, but it's really interesting.

[@cyipkwun9244]

how can we try this puzzle online?

[@WillieZenk]

I've created a link to this one, but YT won't let me paste a link. Let me see if I can guide you to it: Google "Simon Tatham's Portable Puzzle Collection". One of the top results should have the words "chiark" and "greenend" in the URL. Choose that one. Click on the "Light Up" puzzle (same thing as Akari). Then under "Game...", click "Enter Game ID". Delete the game ID already there and paste this in: 45x31:Bn1f1fBnBc2zk1i1bBcBdBg0dBc0b1zzb1d1za1dBw3c1v0n1i1n1k1a2uBa2o0nBa0n1i1n1gBnBi0d1aBq2aBd1hBm0k1m0e0o1e1o1l1b1hBa1hBbBi1nBdBcBd0n1v4v1n1d1cBdBnBi2b1hBaBh1b2l1oBe1o1eBm1kBm0h0d1a1q2a0d1i2nBgBn1i0n2a2n1o2aBuBa1kBn0i0n1v1c2wBd1za1dBzzb1bBcBdBg1d1c0b1iBzk2c1n2fBf0nB I hope that works for you! I've also tested this Game ID with the Android & PC versions of "Simon Tatham's Puzzle Collection" and it seems to work for me.

[@TirianMassot]

@@WillieZenk Thank you!

[@jonathan-._.-]

reactangles can also restict positinos outside of the rectangle if there are no blocking block in the 2nd line

[@Mephistahpheles]

The logic at @3:40 is the same as the Soduko "X-Wing". Just sayin'.