iiinova — where your digital self keeps evolving

It’s a great pleasure to be able to contribute to this milestone 500th puzzle in this way. Thank you for solving it.

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I decided to incorporate not just the visual aspect but also the logic of “confirmation through filling in a long row of ×” and as a result, the logic that confirms Akari in R17C4 serves that purpose.

I considered using the No.381 format because it would definitely get the self-introduction across more clearly, but since I have memories attached to No.336, I decided to base this one on that instead.

Many of you might be wondering,“Where exactly?”. But No.336 was designed with the image of "key and keyhole". I created No.336 with the idea of inserting key when the second Akari was lit. So, regardless of whether the key motif actually came across, that part serves as a sort of self-introduction.

I was assigned the bottom-left section this time, but while I was brainstorming ideas, the board construction was completed by the master creator, mrsdot. This time, I packed the essence of No.336—my very first adopted puzzle—into the bottom-left.

Singfisher Games (Daily Akari) @singfisher.com · 20/05/2026

Message about Daily Akari No.500 (which I collaborated on) It's gotten a bit long, but I really hope you'll read it. ↓

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Reposted by hyd0708

Today's (Wednesday's) Daily Akari is incredibly special! In celebration of the 500th puzzle, a bunch of puzzle constructors / fans have banded together to make this epic board with references to past puzzles! Thank you so much!! 🙇 dailyakari.com

dailyakari.com

Daily Akari

Light up, make happy.

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hyd0708 @hyd0708.bsky.social · 19/05/2026

Today is the memorable 500th puzzle of Daily Akari. Today’s puzzle is credited to “Akari部からの挑戦状”(“Akari Addicts”), made through the massive collaboration of Akari Addicts.……Including me!

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Reposted by hyd0708

Akane @daily-akane.bsky.social · 19/05/2026

■━━━━━━━━━━━━━━□ ┃ 　　2026/5/20　挑戦状　　 ┃ ┃　　 Daily Akari No.500　　 ┃ □━━━━━━━━━━━━━━■ dailyakari.com

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I’ve included an image of the correct solution below. Thank you for your hard work.

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Once you mark this X, you’re almost there. Starting from the 2 in the center, the clues for the areas other than the four corners will be filled in one after another, and the placement of the four corners will naturally fall into place as well.

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In other words, the four red lines are all used up—three by the top-right corner plus one by the top-left or bottom-right—while the four blue lines are all used up by the remaining three in the top-left or bottom-right plus one in the bottom-left. Consequently, the Xs are placed as follows.

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The results of the experiment show that we must avoid placing the X as shown in the third image of the previous post. To do so, we must place Akari on one of the red circles in the image; doing so confirms the 1 in the top-right corner that we discussed at the beginning.

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Let’s try a little experiment. Suppose the number in the block marked with the red circle in the upper right were 0 instead of 1. In that case, the sequence would proceed as shown in the image, and the blue circle marked 1 would break down.

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