* ActingForTwo: Both Eltnum and Uzuki are voiced by Creator/SatomiAkesaka.
** Also, both Linne and Kuon are voiced by Creator/AyaneSakura. Funnily enough, they're siblings.
** There's also Sakurai and Young Seth, who are both voiced by Aimi.
* ColbertBump: Was initially a CultClassic, but featuring it in ''VideoGame/BlazBlueCrossTagBattle'' did alot to boost its popularity, namely by introducing it to three [[VideoGame/BlazBlue much]] [[VideoGame/Persona4 larger]] [[WebAnimation/{{RWBY}} fanbases]].
* MarthDebutedInSmashBros: ''Both'' of the [[GuestFighter Guest Fighters]], as there had not been a ''MeltyBlood'' or ''AkatsukiBlitzkampf'' game released overseas at the time ''Exe:Late'' was released in western countries.[[note]]Although the most recent ''Melty Blood'' game did get a Western release after the fact.[[/note]]
* NoDubForYou: It ultimately took an appearance in ''VideoGame/BlazBlueCrossTagBattle'' for the characters to get a dub.
* TheOtherDarrin: Rather than Creator/RioNatsuki voicing for Eltnum just like her ''VideoGame/MeltyBlood'' counterpart, Creator/SatomiAkesaka takes over instead.
* RelationshipVoiceActor: Creator/YuukiKaji, Creator/YoshitsuguMatsuoka and Creator/SaoriHayami would go on to [[RoleReprisal reprise]] their respective anime characters in the later French Bread-developed fighting game with the same type of HD engine, ''VideoGame/DengekiBunkoFightingClimax''. Creator/SatomiAkesaka along with one other person also narrate the official character tutorials for said game.
** [[Creator/YoshitsuguMatsuoka Chaos]] himself has several:
*** He and [[Creator/SaoriHayami Orie]] while they've fought each other in the chronicle mode, [[LightNovel/TheIrregularAtMagicHighSchool let's just say the former has unrequited feelings for the latter]]. Orie also has [[Creator/SomaSaito Londrekia]] and [[Creator/RyoheiKimura Hyde]] as fellow classmates (the latter even outside of their universe).
*** Both Chaos and [[Creator/ShizukaIshigami Wagner]] are [[SupremeChef supreme chefs]] [[Manga/ShokugekiNoSoma duking it out with orgasmic food, only the latter is a meat expert]]. [[Creator/YuukiKaji Seth]] also annoys Chaos all the time with calling him "Yuki-chin" all the time in that same series.
*** Chaos has gotten himself in a loop with [[Creator/SaoriOnishi Phonon]] as [[LightNovel/HowToRaiseABoringGirlfriend one love interest out of a few]]. [[Creator/SomaSaito Londrekia on the other hand is just minding himself as someone else's cousin]].
*** Chaos even ended up with [[Creator/SomaSaito Londrekia]] [[Manga/AkameGaKill in the same assassin's guild]] and they both end up rebelling against [[Creator/SatomiAkesaka Eltnum/Uzuki]].
** Later on, both [[Creator/YuukiKaji Seth]] and [[Creator/AyaneSakura Linne]][[note]]Or Kuon[[/note]] [[Manga/MyHeroAcademia end up in the same class]].
** To say nothing about [[Creator/ShunsukeTakeuchi Enkidu]] being a producer for a company where the likes of [[Creator/SaoriHayami Orie]], [[Creator/NaoTouyama Vatista]] and [[Creator/AyaSuzaki Mika]] are [[Anime/TheIdolmasterCinderellaGirls pop stars]].
* WhatCouldHaveBeen: Eltnum "Sion" is apparently a built as a test case character for ''VideoGame/MeltyBlood HD'', a game whose development has never come to pass.
** The devs have expressed interest in bringing in a ''VideoGame/{{Skullgirls}}'' character for a hypothetical future build of the game.
*** Specifically, a hypothetical sprite design for Filia has already been done as part of their congratulatory message to Lab Zero after the latter got their game released both in PC and in arcades. This must be in response to Yuzuriha's background cameo in their game.
** Silvaria was originally planned to wield throwing knives when fighting.
** Kaguya was first elaborated upon during a developer stream on upcoming characters where the likes of Chaos, Nanase, Wagner, Enkidu, and many others were shown off. WordOfGod states that Kaguya is taking longer than usual because they wanted to keep Kaguya's playstyle unique and not have a repeat of characters with weapons such as [[Characters/BlazblueCalamityTrigger Noel]] and [[Characters/ArcanaHeart Petra.]]
** Londrekia was going to be made playable and scrapped at the last minute ''twice''. Once during production of the original version of UNIB, where he would've been a puppet character with a rapier and a coffin for his puppet, which were given to Chaos, Orie and possibly Uzuki respectively. The second time was when his design was finalized. As datamining shows, he was given introduction text (as seen on his character page) and a placeholder. To even further enforce this, the game review site GameGrin accidentally leaked Londrekia's character art, which has been since deleted off of the site, but the art can still be found around the web. It's currently up for debate as to whether he will be in the next version/installment or DLC in the possible future.
*** The last point was further enforced when the fighting game coverage site Shoryuken interviewed Kamone Serizawa, French Bread's battle planner. When asked if they are done with EXE: Late[st], Kamone responded that nothing has been set in stone but they are interested in adding more content to the current version. As to whether or not this will include Londrekia is up in the air.