Veil of Mist Warp
Explanation
By doing a very specific Powerslash you warp to the pot which contains mist, skipping getting the key to enter the treasure room. This trick has been patched in the 2017 remasters.
How it works (NG+)
The rope for the pot can be cut from any distance. This was probably done because the distance from the rope was too large so they changed it so the pot was loaded from the very beginning, rather than when you get close. So by angling your camera to a very specific angle and powerslashing in the right spot you cut down the pot. Since cutting the pot triggers a cutscene where the camera is focused on Issun so Ammy is repositioned. So it warps you down at the pot.
Patch
This glitch was patched in the 2017 remasters by making the flask unresponsive to Power Slash until Ammy has watched the cutscene which plays after entering the flask room. Because NG categories are run on these versions, this trick cannot be used to save time in NG All Brushes or Top Dog.
Tutorial
Tutorial for NG+ AB in both 16:9 and 4:3: https://www.speedrun.com/okami/guide/g6ch9
Credits
First discovered by Kwanzai in February 2015 Rediscovered by raku on 25 December 2015 Final setups made by Kyzirado and Kinnin11 at the end of February 2016