History YMMV / HappyDeathDay

* GeniusBonus: Coupled with FreezeFrameBonus. There are two books of sudoku puzzles on the bedside table next to Tree when she wakes up. Sudoku puzzles get easier the more numbers you fill in, similar to how Tree's puzzle gets easier (somewhat) throughout the film by eliminating suspects and murder methods until she figures out who the killer is.

* AlternativeJokeInterpretation: When [[spoiler:Lori and Tree fight at the climax]], Danielle comes by knocking, demanding what the hell's going on in there. Did she (correctly) suspect that [[spoiler:they were fighting or, with their groans and grunts, that they were [[MistakenForGay having sex]]]]?

** The real killer never really crosses this until the penultimate loop. [[spoiler:Tree is being sincere and kind to all the good people in her life, and she gives Lori a heartfelt apology, admitting that she's been a selfish loser and promising to be a better roommate. Lori appears to accept Tree's apology, but then the final loop happens, and it turns out that Lori still gave Tree the poisoned cupcake and freed Tombs as a backup plan in the penultimate loop. And in every loop, Lori is perfectly okay with the idea to release a dangerous SerialKiller on the loose to cover her traces and that in several loops she has no qualms about killing InnocentBystanders, and all of this was because Lori is a {{Yandere}} who wants a teacher all to herself.]]

* NightmareRetardant: In the trailer, Tree's fright at seeing the masked figure for the first time behind her would be understandable... if it weren't for the fact that the mask looks so ''goofy''. Even better: ''That's the mask of the SCHOOL'S MASCOT.'' Though some people [[NarmCharm may still find it scary or disturbing]], due to it firmly falling into the UncannyValley.

* UncannyValley: That weird baby mask. Who thought it would be a good idea to have a school's mascot look like this? (a character in the sequel lampshades this)
* JustforFun/XMeetsY: Many reviewers described the film as ''Film/GroundhogDay'' meets ''Film/{{Scream}}''.

* UncannyValley: That weird baby mask. Who thought it would be a good idea to have a school's mascot look like this?
** a character in the sequel questioned this.

* JerkassWoobie: While Tree is quite dismissive and hostile towards a majority of the people around her, it's made that it's mostly because of her inability to give her mom's death and to reach out to other people. She does eventually get better, but only through the TraumaCongaLine of ''dying horribly over and over''.

* EnsembleDarkhorse: Tree's love interest Carter Davis and her sorority sister Becky Shepard have both been very well liked by the fandom.

* JerkassWoobie: Tree's mom died on her and Tree's shared birthday. This is very sad and gives Tree understandable issues, but she treats every single character horribly at one point or another. She does eventually get better, but only through the TraumaCongaLine of ''dying horribly over and over''.

* NarmCharm: As the straight horror film it was marketed as, the title sounds ridiculous. As the not-so-serious [[SlidingScaleOfComedyAndHorror comedy horror]] it really is, it's not too inappropriate.

* SoOkayItsAverage: It's been accepted that while the movie doesn't add anything new, it's surprisingly entertaining and manages to achieve what it wants, against expectations (as [[NeverTrustATrailer advertising]] made it seem like it was a cheap try at a clichéd JumpScare horror movie).

* AlternativeJokeInterpretation: When [[spoiler:Lori and Tree fight at the climax]], Danielle comes by knocking, demanding what the hell's going on in there. Did she (correctly) suspect that [[spoiler:they were fighting or, with their groans and grunts, that they were [[MistakenForGay having sex]]]]??

** The real killer never really crosses this until the penultimate loop. [[spoiler:Tree is being sincere and kind to all the good people in her life, and she gives Lori a heartfelt apology, admitting that she's been a selfish loser and promising to be a better roommate. Lori appears to accept Tree's apology, but then the final loop happens, and it turns out that Lori still gave Tree the poisoned cupcake and freed Tombs as a backup plan in the penultimate loop. Audiences may forget this when saying that Tree should've just tried apologizing again. There was no chance of changing Lori's mind before it was too late. And let's not forget that in every loop, Lori is perfectly okay with the idea to release a dangerous SerialKiller on the loose to cover her traces and that in several loops she has no qualms about killing InnocentBystanders, and all of this was because Lori is a {{Yandere}} who wants a teacher all to herself.]]

** In this film, Carter is very selfless, even going so far as to [[spoiler: [[HeroicSacrifice sacrifice himself]] to let Tree escape from the killer]]. [[Film/TruthOrDare A later Blumhouse film]] also features a character named Carter, who is [[DirtyCoward the exact opposite]].