"Avidyāic Reversed Flow"
Signature technique of the blind swordsman Irako Seigen from Shigurui.
Performing this technique involves sticking the sword into the ground before unleashing it upwards in a single powerful vertical strike. The first part of the technique is often parodied in other works, with characters being depicted holding a long-shaped object pointing downwards to the ground while leaning their upper body and head almost 90 degrees to the right, similar to the stance assumed by Irako Seigen.
Original scene cropped image posted on someone's Twitter.