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Arizona Chess
Sometimes, you have to sacrifice pieces to gain the advantage. Sometimes, to advance ... you have to fall back.
Title text: Sometimes, you have to sacrifice pieces to gain the advantage. Sometimes, to advance ... you have to fall back.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a DAYLIGHT SLAYING BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.

White Hat and Cueball are playing a timed game of tournament-style chess. White Hat has the advantage, because he has one more pawn than Cueball and has more time on the chess clock, 6 minutes and 35 seconds, versus Cueball's time counting down from 28 seconds at the start of the comic.

However, Cueball has an unexpected advantage. The building is sited across the border of Arizona with another state, with White Hat on the Arizona side, and the game is being played at a very particular time of year, when (most of) the United States exits Daylight Saving Time, which happens at 2:00 AM on the morning of the first Sunday in November. As Arizona doesn't observe Daylight Saving Time (DST), unlike neighboring US states, only one clock gains an hour. White Hat's time remains normal, but Cueball's time "falls back" one hour, as his departure from daylight saving time occurs. Due to the way the timer clock apparently calibrates its display (perhaps in part based upon something like the self-adjusting localtime() function), Cueball is suddenly given more time in the game. White Hat, whose clock is governed by a different locale, protests, as this is not typically how these clocks should function. Daylight *Slaying* Time is a pun on Daylight *Saving* Time, but note that the comic takes place as the non-Arizona clock joins the Arizona clock in Standard Time.

The title text is a pun on "falling back" strategically from an attack and the term "fall back" in the mnemonic used to remember which way the clock changes when we go in and out of DST: "spring forward, fall back" (we advance the clock forward when entering DST in the spring, and move it backward when leaving it in the fall or autumn).

A handful of buildings even extend across international boundaries (these are known as line houses) and many more cross state or local boundaries in the US (a city, county or tribe may sometimes decide to use a different time zone than the rest of the state, so any of these can become a zone boundary, whether or not international databases reflect it). While it is possible to arrange a table across a timezone boundary, a bigger challenge is to arrange the chess clock. Most do not account for timezones at all and are at most about 12 inches across, not far above the positioning error in GPS. Cueball would have needed to find a clock that was capable of tracking time zones separately for each of the two internal clocks and either had an excellent GPS receiver for each side (capable of detecting a several-inch difference in position as corresponding to another zone) or a way to manually enter two different zones, while also having the time-tracking oversight described above. The game could be played in the future where standard chess clocks are different. Ongoing state-level efforts to end time changes could also increase the number of places where this situation could happen.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[White Hat and Cueball are sitting across from each other playing chess. The time, shown above them in white on a black screen, reads 6:35 for White Hat, and 0:28 for Cueball.]
White Hat: It’s late, I’m up a pawn, and you’re out of time. It’s over.
Cueball: Ah, you’re forgetting something.
[Cueball gestures with one hand above the chessboard. His time now reads 0:19.]
Cueball: Did you know this building straddles the Arizona border?
Cueball: It actually runs right through the table. You're on the Arizona side.
[Cueball raises his hand further to gesture at his time. It beeps and is now blank and white.]
Cueball: This tournament started Saturday, November 2nd. Now it's almost 2AM on the 3rd.
Cueball: And there's something you should know about Arizona.
Chess clock: BEEP
[White Hat raises his head slightly to look at the timer. Cueball's time now reads 60:07. Cueball lowers his hand to make a move.]
White Hat: What?! No! That's not how... No!!
Cueball: Looks like it's daylight slaying time.


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