The virtual summer Boswords puzzle tournament is Sunday, July 25. I’m not yet sure if I will be competing, but if you’re still interested you can sign up either as an individual or as a pair.

Today’s tricky puzzle features strings of diagonal circled squares, as well as answers that have two separate clues. 23A says [Ship stabilizer (Final part of a process)] and the answer seems to be BALL. That doesn’t make sense for either clue, so you have to think somewhat outside the box. The first part of each theme clue refers to an answer that starts Across normally (highlighted above in green), then continues diagonally up the circled squares (highlighted, above, in blue). When you reach the top of the circled squares, you either stop right there or you continue on the same line until you hit a black square.

• 23A: [Ship stabilizer (Final part of a process)] is BALLAST. The ballast refers to the “ship stabilizer” clue, starting with BAL and then rising up and to the right with the word LAST. We’ll get to the parenthetical “final part of a process” clue in a bit, but keep it in mind.
• 30A: [Orca’s orifice (Interval between A and B, in music)] is BLOW HOLE, with the diagonal WHOLE.
• 39A: [Abstract expressionist who painted “The She-Wolf” (Form of marching closely together)] is Jackson POLLOCK, with the diagonal LOCK.
• 66A: [Original findings (Go past, as one’s bounds)] is DISCOVERIES, starting with DISC, moving diagonally up with OVER, and then ending on the same line with IES.
• 97A: [It often gets closed at a dealership (Welcome mat’s place)] is CAR DOOR, with the diagonal DOOR.
• 102A: [Drink servers (Maintain the pace)] is BARKEEPERS, starting with BAR, moving diagonally up with KEEP, and ending with ERS.
• 108A: [Weighs (Dodge)] is CONSIDERS, starting with CON, moving diagonally up with SIDE, and ending with RS.

The second part of each theme clue is tied together by the revealer at 114D: [Part of the way up a staircase … and an answer that, when following the circled words, explains seven clues in this puzzle] which is STEP. So let’s look at those seven parenthetical clues:

• 23A: [ … (Final part of a process)] is LAST STEP. You take the diagonal word LAST and add STEP to the end to make sense of that clue.
• 30A: [ … (Interval between A and B, in music)] is WHOLE STEP.
• 39A: [ … (Form of marching closely together)] is LOCKSTEP.
• 66A: [ … (Go past, as one’s bounds)] is OVERSTEP.
• 97A: [ … (Welcome mat’s place)] is DOORSTEP.
• 102A: [ … (Maintain the pace)] is KEEP STEP.
• 108A: [ … (Dodge)] is SIDESTEP.

Ever since the “Lifting Weights” puzzle from this past May — where you took phrases that had the letter string LB and lifted those letters one row above — I’d been thinking of creating a staircase theme featuring diagonal answers. I liked the idea of visually tying each diagonal entry to the word STEP since every letter of the diagonal words represents a step up a set of stairs.

The big problem for me was that diagonal words often cause major havoc in building the grid, even though they don’t take up much space. I learned this the hard way back in September 2018 with my puzzle “Split Ends,” where the theme answers split off in two diagonal directions. The same challenges cropped up again here. Most of my 21×21 crosswords feature somewhere between 90 and 104 theme squares; today’s puzzle has just 63 theme squares. You might think that with fewer letters locked in place it would be easier to fill the grid around them, but diagonal answers constrain you a lot more than normal Across and Down words do.

As an illustration: Imagine that BLOW HOLE were a normal Across answer, as shown in the picture to the right. It would contribute letters to nine different answers — its own Across space and the eight Down answers crossing it. When the letters of WHOLE are diagonal, though, the entry BLOW HOLE now contributes letters to 13 different answers — eight crossing Down entries as before, but now five Across entries instead of one.

Essentially, every square in a diagonal word is pulling weight for three different answers instead of two. That means that though diagonal answers take up the same amount of physical space as they would if they were regular Across or Down answers, filling the grid becomes much more challenging when the letters are spelled diagonally. That’s why there are considerably fewer theme squares than normal, and also why there are far more black squares than you would usually see.