Clair Obscur: Expedition 33 – Sirene’s Dress Guide (How to Enter & All Rewards)

Trying to explore Sirene’s Dress in Clair Obscur: Expedition 33? Here’s how to unlock the area, beat the Chromatic Glissando, and grab every reward inside.
🎭 Clair Obscur: Expedition 33 – Sirene’s Dress 100% Guide
Sirene’s Dress is one of those optional areas in Clair Obscur: Expedition 33 that’s easy to miss but 100% worth your time. It’s tucked away on the east side of Sirene island, and while you can technically visit it early, you’ll run into a big ol’ locked door unless you’ve triggered the right event.
If you’re stuck on how to open that door (or just want to know what’s inside), this guide’s got you covered.
🗝️ How to Unlock Sirene’s Dress
You’ll find the portal to Sirene’s Dress on the eastern edge of the island — pretty easy to spot once you’ve got access to that part of the map. That said, before you go running in, you’ll need to trigger Lune’s Level 6 relationship event.

Here’s how to do that:
- Head to camp and interact with Lune.
- Choose to “spend time” with her.
- You can start this after beating the game’s final boss.
Once you’ve started her Level 6 event, enter Sirene’s Dress and walk up to the locked door just past the expedition flag. You’ll be prompted to “play music” — go ahead and do it. A short cinematic will play, and just like that, the door opens.

🐍 Boss Fight: Chromatic Glissando
Not long after you get through the door, you’ll run into the Chromatic Glissando, which is the main boss of this area. It’s not too bad if your team is leveled and geared, but here are some tips to make the fight smoother:
🔍 Weaknesses & Strategy:
- Target the tail! There’s a weak spot at the tip of its tail. Hitting it with Free Aim will nerf its tail-based attacks.
- It can regrow its tail, though — so be ready to destroy it more than once.
- Keep your team healthy. If a party member dies, the Glissando can consume them to heal itself. Use Healing Tints, or bring a skill like Lune’s Revitalization to stay topped off.
- After you beat it, it’ll spawn three floating enemies.
- Best strategy? Equip Painted Power and Augmented Counter Pictos to unleash massive counterattacks and clean them up fast.
- Best strategy? Equip Painted Power and Augmented Counter Pictos to unleash massive counterattacks and clean them up fast.

🎁 Rewards for Beating Chromatic Glissando
Here’s what you get once the Glissando’s down:
- 567,000 XP
- 13,724 Chroma
- Choralim (Lv. 20)
- Ballaro (Lv. 20)
- 2x Grandiose Chroma Catalyst
- 5x Colour of Lumina
📓 Collecting the Expedition 46 Journal
Keep following the path after the boss fight and you’ll find the Expedition 46 Journal waiting for you. Once you grab it, backtrack to the portal and leave the map — this will trigger the ending to Lune’s Level 6 relationship event.
It’s a really meaningful moment if you’re invested in Lune’s story, so make sure to soak it in.
Sirene’s Dress might be off the beaten path, but it’s got one of the better hidden boss fights in the game, plus some juicy endgame rewards. If you’re gunning for 100% completion (or just want to wrap up Lune’s arc), don’t skip it.
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