If you are the kind of player who likes finishing a run with the best gear, the most powerful upgrades, and a clean trophy or achievement roadmap, Clair Obscur: Expedition 33 has a handful of missables that deserve real attention. The good news is that most collectibles can be cleaned up later. The bad news is that a few key items and rewards are tied to one time moments, specific choices, or side content that becomes inaccessible once you push the story forward.
This guide prioritizes missable items that are either powerful, limited, or directly tied to trophies and achievements, instead of trying to list every single pickup in the game.
How missables work in Expedition 33
Expedition 33 leans heavily on autosaves, and several missable rewards are tied to “confirm” moments where the game clearly signals you are about to move on. That structure is helpful, but it also means you should build one habit early: whenever the game asks you to confirm leaving an area or ending an event, treat it like a point of no return and do one last sweep.
The second habit that saves runs is camp discipline. Optional camp interactions can gate important collectibles, and it is easy to tell yourself you will do them later, then realize the story has advanced past the trigger window.
Prologue missable: The Mime in Lumière (trophy and record)
The single most famous missable in the game happens almost immediately.
While you are free to explore Lumière during the Prologue, you can find and fight an optional Mime before the story event that changes the city’s state. Defeating it is tied to a trophy or achievement that you cannot earn from later Mimes. In practical terms, that means if you skip this one encounter, you are signing yourself up for a second run or a New Game Plus cleanup.
This fight is also worth doing because it tends to align with other early completion goals. It is a great low pressure way to practice parries and dodges, and it often rewards a music record tied to the broader “collect all records” objective.
If you only remember one thing from this article, make it this: fight the Prologue Mime before you advance the Lumière story.
Festival tokens: The Old Key is the missable that quietly breaks completion runs
The Festival segment in the Prologue is where a lot of players accidentally sabotage their own trophy run, because the rewards look like flavor items at first glance.
You can earn tokens during the Festival and exchange them at booths for unique rewards. One of those rewards is the Old Key, and it is the important one. The reason is simple: the Old Key is used later to access a journal that is required for a journal collection trophy or achievement. If you leave the Festival without buying the key, you can be locked out of that journal for the entire playthrough.
Even if you do not care about journals for narrative reasons, completionists should treat this as mandatory because it is directly tied to the “find all journals” requirement.
My practical approach here is straightforward. Spend your first token on the Old Key immediately, then worry about everything else afterward.
The Weird Pictos trade: Easy to overlook, useful to have
Another Festival reward that is worth thinking about is the Weird Pictos. On its own it is not necessarily game changing, but it can be traded later with a merchant for a strong Pictos upgrade that boosts free aim damage and comes with useful secondary stats.
If you are building around characters that frequently use free aim to control fights, break paint nodes, or squeeze extra damage during turns, this can be a meaningful power bump. It is not as critical as the Old Key for trophies, but it is the kind of “quiet value” item that feels great to have in the midgame.
Act 1 missable: The Medalum weapon from the Gestral Village tournament
Act 1 has a missable weapon reward that is worth prioritizing because it can shape a build for a long time.
In the Gestral Village, you can participate in a tournament. The important detail is that you want to win with Maelle to earn the unique weapon Medalum. The weapon is especially attractive if you like Burn focused setups, because it directly supports that playstyle with stance and Burn related effects.
You can win with other characters, but the reward changes, and you may end up with something far less special. If you are the type of player who enjoys building Maelle into a signature damage dealer, this is one of those “do it now, thank yourself later” rewards.
Act 1 missable: A time limited quest reward with upgrade materials
There is also a side quest thread in the Gestral Village involving a character working on the “Ultimate Sakapatate.” The completion path involves finding a specific quest item while exploring Esquie’s Den, then returning to complete a duel for rewards.
The reason I am calling this out in a missables guide is that the quest chain can become unavailable after Act 1, and the rewards include valuable weapon upgrade materials and a cosmetic outfit. Even if you do not care about outfits, upgrade materials are always relevant because weapon progression in Expedition 33 is one of your biggest power levers.
If you are trying to avoid unnecessary grinding later, grabbing upgrade material rewards when they are offered is simply efficient.
Act 2 missable weapons: Clear the Vales before the Axon
Act 2 is where the game starts rewarding exploration with build defining weapons, and it is also where a lot of players unknowingly trip over a point of no return.
Around the Axon progression, there are side areas tied to the emotional “Vales,” and each one culminates in a Mask encounter. If you advance into the Axon fight without finishing these side areas first, you can lose the chance to fight the Masks, and that can cost you unique weapons tied to those encounters.
The weapons commonly called out as at risk here are:
Clierum for Maelle, Chapelim for Lune, and Boucharo for Monoco.
Even if you are not actively using one of those characters at the moment, unique weapons have a habit of becoming relevant later when you respec your party, chase mastery trophies, or pivot builds for endgame fights.
If you want a clean run, handle the Vales before you commit to the Axon.
Act 2 missable record: Camp interactions matter more than they look
If you are going for the “collect all music records” trophy or achievement, Act 2 contains a missable record tied to an optional camp interaction.
After defeating the first Axon, returning to camp can unlock an optional scene. If you do not trigger it in the correct window, you can miss the record reward. The safe habit here is easy: every time you are placed in camp after a major event, choose the option to check up on the others until no new interactions appear.
Even if you are not chasing full completion, music records are one of the more satisfying collectible sets because they reinforce the game’s tone, and collecting them tends to align naturally with doing the best side content.
Act 3 missables: Limited upgrades and “one shot” challenge rewards
Act 3 is less about missing random chests and more about missing opportunities that are limited per playthrough.
One example is a Perfect Chroma Catalyst, which is used for top tier weapon upgrading and tends to be a bottleneck item for players pursuing full weapon progression. There is a particularly easy to miss source of one catalyst tied to a Prologue interaction and a later return to Lumière. If you spoke to the right NPC early, you can claim the payoff later. If you did not, that reward never happens, and since these catalysts are limited, it is effectively a missable power spike.
There is also optional challenge content where you may be asked to accept a fight on someone’s behalf. Declining or failing can remove the content and lock you out of a unique cosmetic reward. Cosmetics are not always relevant to trophies, but they are still “special items” in the sense that you cannot simply come back later and grab them when you feel like it.
A practical missables routine that keeps your run clean
If you want a simple operating procedure that prevents almost every painful miss, follow this rhythm:
In the Prologue, defeat the Mime in Lumière before the story changes the city.
During the Festival, buy the Old Key with your first token before anything else.
In Act 1, win the Gestral Village tournament with Maelle to secure Medalum.
In Act 2, fully clear the Vales and their Mask fights before you commit to the Axon.
After major story beats, always exhaust camp interactions until they stop updating.
In Act 3, treat limited upgrade materials like Perfect Chroma Catalysts as high priority detours, especially when tied to earlier NPC interactions.
That set of habits keeps the run flexible while still protecting the items and collectibles that matter for both power and completion.