In Chapter 5 of Black Myth Wukong you can talk to an Ox NPC “Pale-Axe Stalwart”. He gives a quest to hunt down the five Element Carts. This quest leads to the Secret Chapter 5 area.

Quest Start: Woods of Ember > Ashen Pass I: From this shrine go to the next corridor where a lot of bulls and undead soldiers are fighting. A miniboss will spawn here called “Pale-Axe Stalwart”. Defeat him, then talk to him until he repeats the same line of dialogue. He gives you the quest to find all Five Element Carts in Chapter 5.

Five Element Cart Locations:

1. Brown-Iron Cart – Woods of Ember > Ashen Pass I: From where you fought Pale-Axe Stalwart go up the stairs to find this boss. Story-related, unmissable.
2. Gray-Bronze Cart – Woods of Ember > Height of Ember: Where you defeated Father of Stones open the gate, then go through the next cave and follow the linear story path to reach this both. It’s blocking off the story path. Story-related, unmissable.
3. Crimson-Silver Cart – Furnace Valley > The Emerald Hall – Automatic story-related boss, unmissable, found on main path up the stairs.
4. Horse NPC Cart – Furnace Valley > Valley Entrance: From the shrine go down the path and enter the lava lake on the right. In the corner is a cart stuck inside the lava, surrounded by enemies. Pull the string that’s hanging from the front of the cart to exhaust all dialogue. Talking to this cart only results in the same line of dialogue, the horse NPC is stuck in the cart and wants to be left alone. (We’ll come back to this after Chapter 5)
5. Rusty-Gold Cart – Field of Fire > Fallen Furnace Crater: From Fallen Furnace Crater turn around, backtrack down the path where the big ball was rolling earlier on the way to this shrine. Halfway down the path, on the left, the rolling ball will have destroyed a barrier. You can now go down the left, follow that new path to reach Flint Vanguard boss. After him go down further until you reach the shrine “Cooling Slope”. After this you will see a big frozen gate. Go near it to spawn the final element cart. If it doesn’t spawn you must exhaust all dialogues with the Ox NPC (Pale-Axe Stalwart) in both his locations: 1) where you first fought him after Woods of Ember > Ashen Pass I. 2) where you defeated Crimson-Silver Cart after Furnace Valley > The Emerald Hall. Then return to the Cooling Slope and the cutscene with the last cart will trigger!

Quest End: Where you defeated the Rusty-Gold Cart, talk to the Ox NPC to the right of the frozen gate.  Then interact with the frozen gate to reach the path behind it. Follow this linear path until you get a cutscene that transports you to the secret chapter 5 area.

Rewards: Secret Chapter 5 Area “Bishui Cave” unlocked.