* ArchiveBinge: Once you've finished the 1.4 million words of the main story up to the end of v3, you can get started on the [=HalO=] Omake Index which has over a thousand links (As of thread 24, the uncompressed list of thread links, chapter links and omake links comes to just over ''thirty-five pages'' in Microsoft Word). And if that's still not enough to sate your interest, take a look at the thread number on the Sufficientvelocity link and multiply the number of completed [=HalO=] threads by 100 pages each, and 25 posts per page. It currently stands at 80,000+ posts.
* BrokenBase:
** The Tarbes arc at the time it was being published was not very well liked by many people who saw it as little more the {{Filler}} put in [[TrappedByMountainLions to give Louise something to do]] though that has largely quieted down as of the second arc with the Pixies better tied in to the main story.
** Louise's actions towards the end of v2.0 massively divided readers, with one group saying she performed the worst kind of privacy violation to 60,000 people in a mad search for power and control which could have lead to the enslavement of all the fae. The other group says that because she was manipulated into the action and she didn't have enough information to make a proper judgement of her actions, she shouldn't be blamed at all, and that everyone who thinks she's in the wrong is being unfair. The arguing was so bad, it led to a temporary CreatorBreakdown.
** [=HaLO=] 3.0: A nice collection of WorldBuilding, CharacterDevelopment, and establishing plot points that will become important later. Or a bloated mess of badly plotted out {{Filler}} and glorified Side Stories.
* CreatorsPet: Dunwell, who's main contributions to Halkagenia Online are being the TokenGoodTeammate to give a face to Reconquista, stops being relevant to the plot after Dunkirk. Triggerhappy admitted this and stopped giving him any scenes halfway through V3, acknowledging that they were bogging down the story.
* EnsembleDarkHorse: Bishop, the head librarian of Arrun's Central Library. Despite limited appearances in the main story, she had many omakes to her name. Mostly likely due to her no-nonsense attitude and [[spoiler:her being the personification of one of Cardinal's subroutines]].
* FanNickname:
** Sir Terrance Dunwell, a.k.a. The Most Interesting Man in Albion.
** Cromwell's Fae zombies are popularly known as Zomfae or Zae.
* MoralEventHorizon:
** Cromwell [[spoiler:turning Aki, Arguile and the other dead SAO players into zombies.]]
** Sir Dunwell was a loyal knight of Albion until the Crown Prince ordered him to destroy the nation's grain reserves, thus starving the entire country, to inconvenience the rebels. The prince's crossing of the horizon triggered Dunwell's FaceHeelTurn, causing him to kill the prince and defect to Reconquista.
** [[spoiler:Sigurd and Ephiael manipulating a traumatized, confused, and emotionally unstable Rip Jack to kill for them as part of their plans.]]
* ParanoiaFuel: The zombies. You won't know they are dead until your best friend/spouse/child stabs you with a kitchen knife, proclaiming your salvation in the name of the Founder.
* TrollingCreator:
--> ''"You know, I wonder what precent of the story decisions are made just to troll the readers at FF.net?"''
--> Triggerhappy: ''"All of them"''
* TheWoobie: Louise Françoise Le Blanc de La Vallière. After spending her childhood ashamed of her lack of magical prowess, being bullied at the Academy, and given the nickname of 'The Zero', she then goes on to prove them 'right' when her familiar summoning supposedly fails. Falling into despair and scared of being sent back home, she's given a second chance under the tutelage of Kirche and Tabitha with support from the Academy, and later manages to proves herself at Tarbes when she defeated Lhamthanc. Afterwards, she starts to become friends with some of the Faeries, including Koko and Botan, even coming to see the former as like her older sister, and slowly but surely breaks out of her shell. [[spoiler:All this comes crashing down when her mother realizes her role in the Transition and tries to protect her by ending her studies and locking her up at home, causing her to despair. And when she accidently provokes Kirche in the midst of her depression, Kirche angrily reveals her role in the Transition, right in front of Koko who takes it badly and attacks. Louise, realizing that she stole the Fae from their home and wrecked her own in the process, falls into complete despair. During which, she's manipulated by Julian into coming with him to attempt to bind the World Tree. After accidently seeing everyone's memories and stealing the World Seed, she falls unconscious and wakes up in Romalia, left with the realization she badly messed up and nearly enslaved the Fae]]. Borders on WoobieDestroyerOfWorlds, considering the implication of her having both Void Magic and [[spoiler:the World Seed]].