You can very quickly Corner Boost by walking backwards off a cliff then downdashing into the corner. This can be done on any cliff or object that can be mantled on.

This is more difficult than other Corner Boost methods and consumes a Stamina bar, but is usually substantially faster.

To execute:

1. Be near or mantle on the cliff you want to Corner Boost off.
2. Jump and hold the backwards movement key.
3. Downdash into the corner and press the jump key to wall jump. If done correctly, you should corner boost.