Players exploring the Chasm region in Genshin Impact will eventually hit a dead end. There is a path in the Abyssal Underground Mines area that is completely blocked by a massive boulder. Players attempting the Chasm Delvers quest line must destroy the blockade with a nearby cannon.
How to activate the Mountainator cannon
Before you can fire the cannon, you need two keys to access the gunpowder storage. Once you interact with NPC Jinwu during the Chasm Delvers questline, the locations for both keys will be automatically updated on the map. However, these keys are hidden, and you need to take a few extra steps to get them.
To get the first key, go to the location near the small pond in Underground Mines. There are a lot of mobs in the area so make sure you defeat them before trying to get the key. When you’re defeated, look for a wooden frame leaning against the wall. Just below the frame there should be an explosive barrel that you need to attack once. This will instantly blow up the wooden frame, revealing the key.
The second key is on top of the still. There is a round structure on the Still Water Barrel that you need to break. Once you’re done, you’ll have the opportunity to examine the structure, which will ultimately give you the key.
After getting both keys, go to the gunpowder storage and acquire the cannonball. You can now load and activate the cannon. However, before you can fire the cannon, you need to change the frequencies of three lamps according to the Safe Blasting Device Signaling Guide. Once you’re done, you can fire the cannon to clear the boulder blocking the path.
https://www.gamepur.com/guides/how-to-activate-the-mountainator-cannon-in-genshin-impact How to activate the Mountainator cannon in Genshin Impact