Hunt for dead boxes

2024-01-26

Andrej Cerjac just made a nice circular level:

The Original

Title: AC2024/Level 3
Author: (DrFogh) + AC
Date: 2024-01-25

Titulated me as coauthor (Thank you) but the level is completely new. Only with a design slightly similar to my circular level “Club”.

Anian claimed 13 boxes out of 31 movable boxes are dead (Not needed to move to solve the level).

An extra challenge with circular levels (and levels with one or more boxes on goal at the beginning) is to figure out if one or more of these boxes need not be moved(=a dead box).
Far more challenging than finding fewest pushes or fewest moves since no optimizer or solver searches for dead boxes.

Before the hunt can begin the level needs to be solved. Manually or a solver?
I was lazy and tried Festival. Time out. No solution.
Well, I can help Festival a bit. Stoned all dead boxes, all deadlocked boxes and 2 boxes at positions (J7 and H11) that can’t be reached again if the box is moved:

Normalized

To my surprise Festival managede to solve the level. Solution 552/106 optimized with YASO. Festival moved every one of  31 movable boxes. So no help with dead boxes.

If a level contains lot of dead boxes sometime the reason is a flaw in the design so part of the level simply isn’t needed.

That west wing looks really suspicious. If you can push the starting box(G10) one move up and later one move down you simply doesn’t need it. I cut it off:

No West Wing

A qualified and correct guess. 541/96. Damn! The West Wing totally unneccessary.
6 found, 7 to go.

Now what? It might be possible to pass The South Wing by just moving a few boxes at the top:

Small South Wing

Stoning the lower 3 boxes in the South Wing. And why not try I17 at the same time. Looks unneccessary.
Correct diagnosis. 4 more found. 3 to go. 525/92.

What now? Probably no more groups of boxes to remove. Single boxes?
You need to go round the level to push G10 back to its starting position. The first 8-10 moves are nearly 100% given and when you arrive at the east wing Q9 looks very determined to stay where it is. Let’s try to stone that. And J4 and L15 and thats all Folks. Experienced guesses will get you faster to the goal but you can try stoning the rest of the boxes one by one and get the same result as me:

Cleanup

18 found. Zero to go.  501/84. It is probably possible to find shorter solutions by moving more boxes but that’s not the theme.

Diagnosing dead boxes are one way to improve a level. Sometimes you can get everything to move. Not the case here.
To get something to move just force the player to push a few boxes up against a wall. I just did that with G10 and this is my best attempt:

Final

AC2024/Level3 Remodel
Author: AC and DrFogh
Date: 2024-01-26

And how many dead boxes?

Final normalized and dead boxes stoned

Actually the level has not 31 but 32 movable boxes  because G11 now is reachable. 28 boxes need to be moved. 5 dead boxes. My best 639/96.

Can you find more dead boxes?
Can you change the level so more boxes need to be moved?
The only rule: The box layout can’t be changed.

Festival didn’t solve the changed level.
Neither before nor after normalizing the level.

You are on your own!