Quick answer
The deserted-island trip is a fixed three-week summer event. Meals are free while you are there, and the choice the page is named after comes up whenever the dragon eats an area: eat everything for larger stat gains and a push toward WILD, or leave some for the environment for smaller gains, one skill, and a push toward RULE.
Exploration then splits into two routes. The coast route hands out a random artifact and consumables; the forest route leads to a sealed shrine, the hidden boss Octanya, and the Call the Storm skill that community guides use to trigger a hidden ending.
The three weeks, and why they are worth planning
The Japanese wiki puts the trip between July week 4 and August week 2; the Korean wiki describes it as an event that always happens four weeks after the first act boss. Both point at the same stretch of the calendar, and neither gives an official confirmation of the other’s wording.
Food costs nothing on the island, which makes the trip a free stat window. The Korean record lists three kinds of island food: a cheap option that gains a little and restores 30 stamina, an option that raises one stat while lowering another, and an option that raises two stats at once for 35 stamina.
After eating, the week is spent on either resting — recorded as a full stamina recovery — or exploring, which costs 35 stamina. The same record advises filling all three weeks with exploration if your stamina allows, because the rewards are what the trip is for.
Eat everything or leave some behind
| Choice | Recorded effect |
|---|---|
| Eat everything | Three random stats increase three times each, and the personality shifts toward WILD. |
| Leave some for the environment | Three random stats increase twice each, you learn one skill, and the personality shifts toward RULE. |
The Japanese wiki records the same two options in their in-game wording, and adds a second pair of beach choices that appear to affect only the kind or strict record rather than the personality bar. That reading comes from the wiki author’s own analysis, not from the game’s documentation.
Coast or forest: the real branch
| Route | What it gives |
|---|---|
| Coast line | Cave and trash-mountain areas. Eating the rock field opens up movement to the dump and the cave; clearing the dump yields a large number of mysterious paper fans, and the route hands out one random artifact plus consumables. |
| Forest line | Forest to waterfall. You learn a skill, and if you let the dragon eat the sealed shrine, the seal breaks and Octanya appears. |
The forest route is the one with consequences beyond the trip. Defeating Octanya grants Call the Storm, and community guides describe using that skill at maximum level inside a single battle to trigger a hidden ending and its achievements. The official achievement for defeating her sits at 39.9%, which makes this one of the more commonly seen optional fights.
A Steam player describes the practical route as visiting the forest location twice and taking the top option on the second visit, then agreeing to eat the shrine; the same post notes that poisoning Octanya made the fight manageable. The Japanese guide phrases the same chain as Forest → Waterfall → eat the shrine.
How thin this evidence is
This is one of the least documented parts of the game in English. There is no dedicated English page or video for the island event, and the numbers above come from one machine-translated wiki unless another source is named. The trip’s records predate version 1.0, so anything added or rebalanced with the release would not appear in them.
Two versions of the same chain also circulate — “visit the forest twice” and “Forest → Waterfall” — which may be wording for one route or a change made when Octanya was added in October 2025. The endings page and the random-events page pick up the parts of this chain that lead elsewhere.
Sources
The Octanya achievements are official and were checked on 29 September 2026. Route and reward details come from community sources, including one machine-translated wiki.
- Steam global achievement stats — DRAPLINEOctanya Conqueror and the storm-level achievement, read 29 September 2026
- h1g DRAPLINE wiki — game flowcommunity wiki, July week 4 to August week 2 window, trash mountain rewards
- NamuWiki — DRAPLINE, summer vacation eventcommunity wiki, three-week structure, food options and route split
- Shiranami Gamer — achievement guidecommunity guide, Forest → Waterfall → shrine → Octanya chain
- Gamerch — Aura conditions (beach choices)community wiki, in-game beach option wording
- Steam discussion — new events and achievementscommunity post, reproducible forest steps and poisoning tip
Page added 29 September 2026. Source check performed 29 September 2026.