• Cap’n Freeman’s log records the stardate as 58759.1.

• The world of Corazonia is an artificial ringworld circling a star. In “Rosetta” and “Coming Home” we saw that Species Ten-C used similar Dyson rings to harvest energy from the stars of their original home system, and their newly established home.

     • The scale of Corazonia and its star is…questionable, but that’s hardly a new issue in Trek. Consider the USS Voyager traveling through the planetary ring in VOY’s title sequence, or the utterly massive Borg cube being visible in Jupiter’s eye in the PIC finale, “The Last Generation”.

     • Not canon, but Corazonia very much resembles the Ringworld from the cover art of Larry Niven’s 1970 novel, “Ringworld”, set in his Known Space series, which is also the origin of the Kiznti.

• Corazonia’s climate is controlled by a sentient computer, Vexilon. Other planet controlling computers have been seen in:

     • “The Return of the Archons” - Landru

     • “The Apple” - Vaal

     • “Spock’s Brain” - The Controller

     • “For the World is Hollow and I Have Touched the Sky” - The Oracle of the People

     • “When the Bough Breaks” - The Custodian

• Freeman roles up her sleeves before getting to work on Vexilon, not unlike the way Mariner keeps her sleeves all the time, despite it landing her in the brig at least once.

• Freeman states that she ”minored in archaic technology back at the Academy.” If Mariner is to be believed in “Room for Growth”, the USS Cerritos has been overwritten by D’Arsay technology three times.

• Boimler’s team’s shuttle is the Kings Canyon, presumably named for Kings Canyon National Park

• ”Statistically, ensigns serving under recently promoted commanders are more likely to experience death and/or dismemberment.” Wesley Crusher’s entire team in “Pen Pals” died during his first time in charge, and he wasn’t even recently promoted.

• Inside the anomaly storage room we see:

     • A probe resembling the Kataan probe from “The Inner Light” but with some notable differences

     • What appears to be an oversized Vulcan lirpa

     • Nomad from “The Changeling”, or a very similar Earth probe transformed into an artificial life form

     • A Wadi board game, from “Move Along Home”

     • What appears to be an empty transport case for a Medusan, including a visor missing the red protective lens; Ambassador Kollos used one in “Is There in Truth No Beauty?”

     • A bat’leth

     • A Betazoid gift box, like the one seen in “Haven”

     • A 23rd century Romulan cloaking device, like the one Kirk and Spock stole in “The Enterprise Incident”

• Billups’ pet ferret is named Lancelot; it was established in “Where Pleasant Fountains Lie” that Billups comes Hysperia, a planet colonized by “Ren faire type” humans.

• Tendi, Mariner, and Rutherford are using T-88 scanners to check the chips in the isolinear chip junction. T-88s were first seen in “Cupid’s Errant Arrow” and weren’t available fleetwide yet, but Rutherford and Tendi did steal a bunch from the USS Vancouver.

• ”Is it a unotronic?” Duotronic and multitronic systems were designed by Richard Daystrom, which we learned in “The Ultimate Computer”. This is the first mention of a unotronic system, though it’s not entirely clear if that’s an actual thing, or simply a bit for Billups’ joke.

• Dirks claims he was trapped in the Wadi game for a month as a child. The Wadi are a gamma quadrant civilization who were first encountered in 2369, 12 years prior to this episode.

• Boimler refers to the large blue guy as ”Big Merp.” In “I, Excretus” the scoreboard showed that another member of the same species was also named Merp. Are all members of the species named Merp? Is it the name of their species and just what they’re all called? Or is Merp simply a common name among their species?

• Rutherford ends up in the Wadi game, where he encounters the same puzzles Captain Sisko, Kira, Doctor Bashir, and Jadzia did in “Move Along Home”.

• Dirks states the Tellarite slop jazz musician Fats B’zirtak overdosed on ketracel-white. Assuming fats was not a Jem’Hadar, I believe this is the first time we’ve heard of a non-Jem’Hadar consuming ketracel-white in canon.

• The Betazoid gift box gets zapped by the not-Kataan probe and experiences an entire simulated life, similar to what happened to Captain Picard in “The Inner Light”, though at no point from Rutherford’s perspective does the gift box appear to be unconscious.

     • ”I miss my wife.” The gift box repeats Michael Sullivan’s line from two episodes ago in “Twovix”.

• After he dies we see Boimler in room which appears to be inspired by the red room from “Twin Peaks” based on the floor pattern, lamp, and end table. Outside the window he sees the black mountain, which Shaxs described as a ”spiritual battleground” in “We’ll Always Have Tom Paris”.

     • The Koala appears, and according to the subtitles it’s ”speaking Koala” but if you reverse the audio it says, “It is not your time, Bradward Boimler.”

     • This is the second time Boimler has seen the Koala, the first being when he nearly drowned in “First First Contact”.

     • Despite being at the Black Mountain, Boimler did not have to fight three faceless aspirations of his father, nor did the surviving father feed Boimler his own heart, as Shaxs described in “We’ll Always have Tom Paris”.

• ”You never forget your first death.” Ransom implies that he too has died.