The version number "1.5.x" signifies a significant engine transition for the game:
Resolved an issue where the Godmaster "Pantheons" would get stuck at the end screen if the player was not using a controller. File: Hollow.Knight.v1.5.75.11827.zip ...
This report provides details on the specific build version 1.5.75.11827 , which was released in June 2021 as part of the game's major v1.5 update. Patch Overview: v1.5.75.11827 The version number "1
The compressed download is approximately 3.1 GB . File: Hollow.Knight.v1.5.75.11827.zip ...
Fixed a bug that prevented language settings from saving correctly when changed while inside the game. Context: The v1.5 "Unity Update"