The demo uses Yasuhiro as the victim to hide the first case's true victim, just like the first game's. Monokuma even lampshades this, stating how this was the "second time" Yasuhiro died.
When Kaede gives Hajime her unconditioned trust in the demo, Hajime declines it by saying if Kaede really trusts him, then she should suspect him first. This is in line with his own game's Case 3, where "belief without doubt is a lie" is the underlying theme.
Kokichi dislikes pork's feet. This could be viewed as a reference to Hiyoko's nickname towards the Ultimate Imposter in DR2 with her calling them "Mr. Porkfeet".
Other items in Mind Mine in the demo besides the kitchen knife are a crystal ball and a dumbbell.
By all initial appearances, it looks like Ryoma's Chapter 2 murder harkens back to an unused execution from the first Danganronpa game. In it, Aoi Asahina was put into a tank for a magic show trick, and when the curtain goes up again, only her bones remained.
Angie's first free time event makes a reference to Jabberwock Island:
Angie: I sorta remember a place like that... Jabba-something Island, I think?
In the Neo World Program, Himiko is disappointed that it's a snowy mansion and chapel, and wishes it was a tropical island.
This game's second execution is based on a short story popular in Japan, just like in Danganronpa: Trigger Happy Havoc. In V3, it's The Spider's Thread by Ryunosuke Akutagawa; in Trigger Happy Havoc it's The Story of Little Black Sambo by Helen Bannerman.
During the third class trial, it was falsely suggested that one of the victims committed suicide just like in Danganronpa 2.
Kaede isn't the first musician in the series to be killed by strangulation with a rope and had her lifeless body left hanging. Additionaly, her execution finishes with a Casting Gag as her body is crushed. It gets even better when it's revealed that the Chapter 1 Class Trial, just like the Chapter 5 Class Trial of the original game, is a Frame-Up orchestrated by the mastermind in order to cover up their own crimes. However, it was possible for Makoto Naegi to outwit the mastermind in the original Danganronpa (and the canonical choice as well), to the point that even when Monokuma attempts to execute him in retaliation he's foiled by Alter Ego. By contrast, the mastermind's scheme goes off without a hitch in V3 as it's impossible to save Kaede even if you're aware of the truth.
Gonta's execution references how the past Chapter 4 killers died, as he was poisoned like Sakura and he was overrun by animals like Gundham. In addition, an AI version of himself is executed as well, similarly to how Alter Ego was executed in the first game.
Just like in the first game, the Chapter Five victim was unknown at the start of the investigation.
Kaito's execution is a recreation of the Headmaster's execution in the first game's prologue. However, Kaito succumbs to his disease before it can be finished.
Tsumugi's skill is called "2D Love" which is a reference to Hifumi's love for 2D Girls.
The third murder involves a katana with gold leaf covering that easily rubs off, just like the first murder of the first game.
During the third trial, Tsumugi suggests that Tenko's murderer may have stabbed her from below by hiding in the crawl space under the floorboards and marking her location with glowing paint, which is how the first murder of the second game was carried out.
Once again, an Alter Ego character comes into play. This time, the survivors use Alter Ego Gonta to find out their motivation for committing the fourth murder, since the flesh-and-blood culprit is suffering from amnesia due to a botched entry into the Neo World Program.
The mastermind's room contains the same type of monitor seen in Danganronpa 3 Future Arc.
The Hope's Peak Academy Monopad theme costs 11037 casino coins.
In K1-B0's event with Miu in the Ultimate Talent Development Plan, she suggests giving him the feature to "cry" juice and tea from his eyes, similar to Mechamaru.
Junko (DR1): In other words, if you see despair as the enemy, then your enemy...is the world itself! Tsumugi: So if you want to make me your enemy...then your enemy is the world of Danganronpa itself!
Then following that she says lines, cosplaying as different characters that are references to things they have said in the past games or that stay in-character: The final piece of evidence that reveals Leon as the first killer in DR1 is when the characters realize Sayaka's dying message was a series of letters not numbers.
Leon: But isn't it just rad how it looks like a letter but it's really a number!
After Nagito earns the prize from the final dead room he learns Hajime has no talent:
Nagito (DR2): An average, talentless human....That's right, you were never an Ultimate! you had no talent whatsoever.
Nagito: You're just normal, average, everyday people, with no Ultimate talent whatsoever.
Chiaki's speech to Hajime during the final class trial in DR2 is said as words of encouragement to inspire the indecisive Hajime to just act, with the faith everything will work out. However, Tsumugi repeats this phrase, telling the V3 cast, they believed in their fake talents so much that just acting upon them led to desirable outcomes.
Chiaki (DR2): I guess what I'm trying to say is... If you just do it, things will turn out okay. Chiaki: Kinda like a form of auto suggestion...you know like if you do it, it'll all work out.
In DR2 Sonia is a serial killer enthusiast. In V3 Tsumugi compares giving the V3 cast fake talents, personalities, and upbringings to what happens in the Netflix series Making a Murderer.
Sonia: Much like that delightful documentary Making a Murderer.
In DR2, Chapter 4's class trial is spurred on due to Gundham's displeasure with his friends resigning themselves to die and no longer trying to live, all to avoid killing each other. Tsumugi uses his line to show displeasure with everyone refusing to vote (grounds for immediate death), to end the killing game with a unsatisfying ending for the audience.
Gundham: Such foolishness! To cast your life away is the height of stupidity./(Non-stop debate) To choose death is a blaspheme against life itself.
In DR2's final trial, after learning they're inside a virtual world, Kazuichi pops up the question of what they are if that's the case, to which Fuyuhiko insists that Monokuma doesn't say that they're fictional characters. When Tsumugi explains their true identities and how they are who they are now, she cosplays as Fuyuhiko saying the following line:
Fuyuhiko: The people you used to be were gone. You're fictional characters now.
The DR2 ending was about Hajime moving to the future with all it's uncertainties, and the importance in deciding your own future. In the same Non-stop debate as above Tsumugi uses it as an excuse for why the V3 cast should move forward.
