MSYS is a very useful shell emulation for Windows as like POSIX and MinGW/MinGW-W64 for help many developers can build almost of source codes for POSIX targets. It may strong POSIX shell like desktop application ever than any other shell emualtor like CYGWIN in personally.
For a long term to using MSYS, I had tired old school shaped icon, so I made an icon as like above image.
Source is here ( a PNG image file ), resolution is 512x512x32bit.
And here more for modified SH.EXE (version 18.104.22.168) that contains my icon as internal resouce. Just overwrite your SH.EXE with mine (and back up ytour previsoud version of SH.EXE to SH.EXE.ORIGIN or SH.EX_ .. )