Budding Leaf and Tiny Ember meet aboard the Firebrand and begin to make plans to use the ship's holodeck to play a 'peaceful' run of Overworld in order to convince the Impact mnemonic virus the Leaf is not so bad a person. Ember also intends to make some improvements to the Firebrand's energy systems to allow more power to be routed to important systems in an emergency.
This is the last thing either of them remember…
(A whole other adventure happens off screen in this interlude. Most details of this become clear during the mission proper (below), but if you require the canonical OC summary for whatever reason, James can provide a copy.)
…until they wake up alongside Charismatic Wheelhouse in what Ember (now dressed in fantasy adventuring gear) recognises as her Vyixian Spa simulation. Despite Leaf being in a holodeck, the Impact mnemonic virus is notably not present. Nor are any of the spa staff, which Wheelhouse remarks is odd. Wheelhouse joins the party for the remainder of the mission.
The party recover their equipment from lockers in the spa. Wheelhouse unexpectedly has a fantasy-style sword; Ember and Leaf retrieve their expected equipment, plus some unexpected fragments of research notes.
Notebook Page 4 lists some holodeck wake words for the 'Firebranch Holodeck (Spa)' and 'Spa Holodecks (Overworld)'. Ember discreetly shares this with Leaf but keeps this secret from Wheelhouse.
Notebook Page 10 is a hurried and unfinished note imploring the reader to find the other pages of the notebook, which have been hidden.
Given this strange scenario, the party decide to explore the spa. Wheelhouse is especially excited to do so, as the spa has become very samey to them and they crave something new and exciting. The party soon finds a door labelled 'Holodeck Room', which Wheelhouse says is new. Ember breaks down the door, only to find no holodecks, but rather that the room warps into a tunnel passage to a ruined dungeon. Following this, the party find themselves in the world of Overworld.
The party are accosted by frogs, which they discover can be rendered docile by telling them several frog puns each; in service of the goal of their 'peaceful' Overworld run, the party pacify all the frogs. The frogs drop some gold, and more notebook pages.
Notebook Page 1 discusses the plan to do a 'peaceful' Overworld run, and appears to have been written by Budding Leaf.
Notebook Page 5 describes that Leaf has somehow managed to talk Impact around to neutrality, and was now silently watching as the party 'prove themselves'. It also mentions that Ember will take over note-taking from this point.
The party move on to a chamber filled with statues, which must be moved in certain fashions in order to unlock doors to progress. Puzzling their way through, the party find three fragments of the same notebook page, which they able to piece together.
Notebook Page 6 chronicles the party's journey through Overworld, on the beginning of a peaceful run: they meet the murderous Terry the Tree and overly protective Guida, both of whom try to kill them. The notes also detail how to pacify frogs (frog puns), ghosts (20 questions), and skeletons (philosophical conversation).
Continuing on, the party find their way blocked by the aforementioned Terry the Tree, who does indeed seem to be very murderous. The party are committed to resolving things peacefully, but Terry is quite insistent on fighting them, and that there is no way he can be talked down. As the battle progresses, Charismatic Wheelhouse is knocked down and swiftly executed by Terry the Tree, before the rest of the party can intervene; this proves to be the catalyst that Tiny Ember and Budding Leaf need to take the fight to Terry and destroy him.
Ember and Leaf tinker to attempt to resurrect Wheelhouse (being a simulation, after all), and are someone successful - Wheelhouse is revived, but is haunted by inexplicable memories and an intense fear of trees.
Terry leaves behind a large pile of gold, which the party elect to ignore in the hope that this won't count as a 'kill' against their peaceful run. Leaf also plants a seedling from their remains in the hope this makes up for things. As they walk away, Leaf hears the seedling call them an idiot. Leaf regrets planting the seedling. Two notebook pages are also left behind.
Notebook Page 2 goes into details about several problems with the plan set out on the Page 1, in particular that deloading the spa program on the Firebrand to run Overworld would risk damaging Charismatic Wheelhouse, and that the mnemonic virus is designed to prevent a peaceful run from being possible in the first place.
Notebook Page 7 continues the chronicling of the party's forgotten first adventure through Overworld: they met Wingding and a 'normal' Impact (distinct from the virus), heard of another character named Aetta, and mused on what the virus Impact's true motivations might be. The note ends with the bemused discovered that Charismatic Wheelhouse has shown up in the run.
Ember and Leaf discuss their discoveries, but are careful to keep from Wheelhouse the notes that reference them being a simulation. However, Wheelhouse becomes suspicious about this, and eventually Ember decides to come clean. Over the course of an extended discussion, she carefully explains to Wheelhouse their true nature - what happened to the real Orion Gate, what happened on Zero Hiding's simulation of the Orion Gate, and the creation of the spa. The end result is that Wheelhouse is left deeply troubled and listless.
Eventually the party proceeds onwards into a forest (Wheelhouse takes some coaxing), where they encounter skeleton guards. Following the instructions from the notes, engaging them in philosophical conversation pacifies them. The party muses over how many attempts they might have previously made at the peaceful run - was it just one, or have they done this repeatedly? - and Leaf leaves a message with the skeletons to be repeated to them 'next time' as a test of this theory. Pacifying the skeletons yields more gold and another notebook page.
Notebook Page 8 explains that the party has let Wheelhouse arrived after finding a Holodeck Room that the party had installed in the spa. They've let Wheelhouse tag along, have found them a weapon, and they seem to be enjoying the new experience. Meanwhile, having pacified Wingding, the party is now going on a dinner date with him! Finally, the note says that the virus Impact and Leaf have gone to have a talk, and that the next note will be Leaf's explanation of the results.
The party arrives at a village, where a manic ball of fluff is selling a variety of items including the final two notebook pages. The party do not have enough gold for both, so Ember decides to backtrack and retrieve the uncollected large pile of gold from the Terry encounter. This allows the purchase of both pages plus some cheese, though some extortionately-priced armour remains out of reach.
Notebook Page 3 details the actual plan Leaf and Ember concocted to work around the issues detail on the second page: they placed two holodecks within the spa simulation, networked together using a fan-made mod for Overworld that links two distinct instances of the game. In this way they are able to avoid disrupting the spa program containing Charismatic Wheelhouse, and also hack around the mnemonic virus interfering with the Overworld game making a peaceful run impossible - with Ember in one holodeck and Leaf in the other, Ember's game can be made authoritative and thus be free from interference.
Notebook Page 9 details the results of Leaf's conversation with the mnemonic virus Impact, after it had observed their peaceful playthrough up to the point of sparing Wingding. Ultimately the virus Impact regrets that it is burdened with meta-knowledge about the game, and wishes it could be more like the regular Impact it has watched the players interact with. Leaf muses in the note that maybe merging the two Impacts together might resolve the virus.
The village also features a restaurant, where the party find Wingding. Wingding explains that during their dinner date, the world fell apart and reformed, seemingly due to something about the conversation with the virus Impact. Wingding also makes it clear that Notebook Page 10 was written by Leaf, not by Wheelhouse as the party had been assuming. Clearly, something that was discussed with the virus had turned its opinion at some point between the ninth and tenth pages. In this new world, Impact is not in a good way has has gone to 'the Laboratory' for some purpose; Wingding implores the party to follow and fix his brother.
On the way to the Laboratory, the party are accosted by unfinished business ghosts. The party do their best to pacify them by asking questions to guess the objects that caused the ghosts' deaths, with mixed results, though the ghosts are eventually pacified. More gold is dropped.
The party reach the bridge to the lab, but their path is blocked by Aetta the Eternal, the realm's ultimate defender. It seems that Impact has briefed Aetta against the party, and she is insistent on attacking them despite the party's protestations. Convinced of the need to remain peaceful, the party hold Aetta off for a while, kiting her across the bridge in an attempt to allow other party members to rush past. Budding Leaf and Charismatic Wheelhouse make it past, but Tiny Ember is struck down by the furious Aetta. Moments from Aetta executing Ember, Wingding intervenes. After a tense negotiation, Aetta leaves Wingding to guard Ember while she pursues the others into the laboratory; Wingding is conflicted but ultimately revives Ember given their established friendship. Ember stays behind to recover, but tinkers her drone to provide support and sends it after the others.
In the laboratory, Wheelhouse and Leaf find several caged monsters and a strange machine. Experimentation reveals that the machine can composite monsters together if the cages are fitted to either side of the machine and a switch pulled. The composite monsters are confused and aggressive, but can be pacified. The pair head into the basement of the lab, where they find the virus Impact, as well as the original Impact held in stasis. Upstairs, Aetta catches up, shortly followed by Ember's drone.
In the ensuing standoff, broken up various skirmishes, the party do their best to negotiate with the virus Impact. Attempts are made to push him into the compositor machine alongside the original Impact in stasis, but the virus Impact becomes wise to this and evades future attempts. At one point Aetta is struck down, but through sheer determination she comes back to fight again; eventually being defeated by Wheelhouse. Ultimately, the virus Impact requests to be given the wake words that will allow them to leave this level of the simulation and take over the systems of the Firebrand; he obtains the words to get to the Spa level but Ember eats the notebook page to prevent him getting the rest.
Virus Impact wreaks havoc in the Spa in his attempt to escape into the Firebrand's systems, drawing the attention of the ship's sysadmins who initiate a system purge. The party do their best to assist, heading in and out of the holodeck at various stages in the chaos. Ember's earlier tinkering allows additional power to be rerouted to help with the system purge.
Realising that the purge will wipe Charismatic Wheelhouse, Tiny Ember persuades them that they can bring them into the real world, and with their consent works with Budding Leaf to extract Wheelhouse's data.
With Leaf out of the holodeck, the virus is no longer afflicting the Firebrand - but Leaf and Ember realises this just puts them back where they started, as the virus is still in Leaf's head. Re-entering the simulation, they use the system purge to burn the mnemonic virus out once and for all.