@echo off
setLocal EnableDelayedExpansion
set mkvmerge=C:\Program Files\MKVtoolnix\mkvmerge.exe
pushd G:\Media\Movies
for /f "tokens=* delims= " %%f in ('dir/b/ad') do (
pushd %%f
set /a N=0
for /f "tokens=* delims= " %%a in ('if exist *.avi dir /b/a-d *.avi') do (
set /a N+=1
set P!N!=%%a
)
if !N! equ 2 (
cls
echo Now Muxing: %%f
"%mkvmerge%" -o "%%~ff.mkv" "!P1!"
echo del "!P1!"
)
popd
)