Alternate Endings

Sid Sivakumar is an M.D./Ph.D. student at Washington University in St. Louis. This is his 15th crossword for The Times in three years.

He likes theme ideas and clues that are challenging but not forced. When you figure something out, he wants you to say, "Of course!," not "Uh ... OK, I get it." When possible, Sid includes South Asian references in his puzzles, as in the clue for 111-Down here.

I sometimes read critiques of crossword themes that feel "computer-generated." I empathize, especially in a time of AI tools that are increasingly capable of humanlike text and art. I did write a computer program to help me identify hundreds of ZIPPER MERGE candidates — but I sifted through the options manually and tried many placements in the grid until I found an arrangement that would fill cleanly.

But the most compelling story behind this puzzle is a personal one: I spotted the central theme answer, HEAD TABLE, on a seating chart my then-fiancée Mahima sent me for our upcoming wedding reception. At the time, I noticed that alternating sets of letters in this phrase were hidden in WILL THAT BE ALL and RED ALERT, but I couldn't find a tidy way to present these curiosities in a crossword puzzle. Six months after the wedding, I merged onto my local highway in rush-hour traffic, and — aha! — the theme mechanism for this puzzle suddenly came into focus.

I don't discount the possibility that AI might eventually make much creative work trivial or even obsolete. But I'm hopeful that nothing will replace the experience of making connections with your own brain.

I spent an hour trying to figure out what was going on, and then another hour coming up with ways to deflect all the incoming questions. ZIPPER MERGES gets at two Down entries heading into one of the five merge spots, at which point, a third Down entry alternates the ends of the first two.

So much for that hour.

Let's try a visual example:

The ends of HOWCANTHATBE and SILVERMEDAL zipper together to form HEADTABLE.

I tried to think of some other way of using visual cues to help this explanation, but the guy in my head kept honking at every idea I had.

Jim Horne and I discussed ways of helping people figure out what was going on, and we landed on the Krakenization seen below. I'm not much of an ice hockey fan, but you gotta love the team making its first playoff and going deep! [The Seahawks, Mariners, Sounders, and Kraken all sport the same color scheme.]

How can you even find pairs that work this way? Well, arrays and dictionary coding constructs allow you to—

HOOOOOONK

I used to love this sort of brain-busting construction — Patrick Berry's simpler implementation blew me away when I first started. I've had so many solvers throw pencils at me over the years, though, that these days, I ease up to be more solver-friendly. I'm ecstatic for those gritty folks who gritted through this one and earned their fantastic a-ha moment — and I'm also sympathetic to those who got too frustrated or even stymied.

Since the Sunday Magazine can employ color, Krakenizing could have been spectacular. Although it would make the concept too simple for some, it would make it much more accessible to a broader audience.