Part I: Spirit of Crate, first crate

To start the secret quest, go to Conclave of the Three and then to the NPC of the Dreeg faction. Behind him is the entrance to the forgotten Cellar. Inside, destroy the Unassuming Crate to make the NPC Spirit of Crate appear.

Part II: Second box

Then go to Temple City of Osyr and then take the secret passage to the northeast, the secret passage leading to Hidden Refuge. The second crate is to the north of it.

Part III: Third box

The third crate is at the Sunbane Oasis. Take the secret passage under the broken bridge as shown in the screenshot to find it.

Part IV: Fourth box

The fourth is on the Ruins of Abyd map, behind the hidden wall north of Vanguard of the Three.

Part V: Fifth crate

For the second to last, go to Valley of the Chosen, behind a breakable wall east of the entrance to the Tomb of Nephos.

Part VI: Sixth crate

The sixth is on the second level of the Tomb of Eldritch Sun, in the hidden part as in the screenshot below.

Part VII: Chillheart

You will need this cutlass to continue the quest. Go to Vanguard of the Three and stay in the green zone. You will suffer damage then after ten seconds the sword will appear (yes, as if by magic!).

Part VIII: Blonebleach Basin

Once all these items are in your possession, go to Cairan docks, northwest at the Crate Entertainment logo. Walk on the logo to destroy the wall (if you have destroyed the seals) and pass. Be careful, you will suffer a DoT due to sandstorms. North of this area you will have an altar to activate thanks to Stormheart. Take the rift to go to the Sanctum of the Chosen and activate the levers in the order of the power of the drops (white, yellow, green, blue, purple)

Part IX: Edge of Reality

You will have three levels to go:

• for the first one, hide among the Oversized Maggot in order to find the "Perfectly Usual Oversized Maggot" and kill it (be careful the others will OS you), it will then open a rift
• the second level is linear, just go to the bottom
• at the third level you will find the Celestial

Part X: Celeste Crate of Entertainment

Once you have overcome all these tests, the hardest part will unfortunately remain to be done! This is one of the more complicated bosses in Grim Dawn if you are not well equipped. Here are some tips:

• The Celestial will send you crates that explode in melee, as well as others that shoot, as well as in the form of meteors.
• Favor a ranged character, there will be too much melee damage
• Max the stolen life, especially via a gunner for example, in order to sustain sufficiently
• Dodge the meteors at all costs, kite the boss and heal yourself with the sustain on his crates

Good luck !