ALL000.MIS contains mission mappings, so it connects mission number with its level and map file name.
Level file names has format:
c<cnum>l<lnum>.<ext>
where
cnum - is a map number (but not the map file number)
lnum - is a number of a specific level on this map
ext - determines the level variant.
DAT - only one variant available, D1...D3 - variant number
So one level = one file => there is 215 levels in the game!!!
(only 108 of them are mapped to levels by the ALL000.MIS)
Level files structure is known, but not all of the values inside structures are identified. Here you can download level reader, which should help in recognizing the rest of level files. The archive also contains Dev-C++ project and Level File Format description.
Download Syndicate Wars Level Files decoder
Partially reworked .\LEVELS files:
LEVELS\ALL000.BEN LEVELS\ALL000.MIS LEVELS\ALL000.OLD LEVELS\ALL001.MIS LEVELS\ALL098.MIS LEVELS\ALL099.MIS LEVELS\C000L001.D3 LEVELS\C000L001.DAT LEVELS\C001L001.D1 LEVELS\C001L001.D3 LEVELS\C001L001.DAT LEVELS\C001L002.DAT LEVELS\C001L003.D1 LEVELS\C001L003.D2 LEVELS\C001L003.DAT LEVELS\C001L005.DAT LEVELS\C001L007.DAT LEVELS\C001L010.DAT LEVELS\C001L015.DAT LEVELS\C002L001.D1 LEVELS\C002L001.D2 LEVELS\C002L001.D3 LEVELS\C002L001.DAT LEVELS\C002L002.DAT LEVELS\C002L003.D1 LEVELS\C002L003.DAT LEVELS\C002L005.DAT LEVELS\C002L007.D1 LEVELS\C002L007.DAT LEVELS\C002L015.DAT LEVELS\C003L001.D1 LEVELS\C003L001.DAT LEVELS\C003L002.DAT LEVELS\C003L003.DAT LEVELS\C003L007.D1 LEVELS\C003L007.D2 LEVELS\C003L007.DAT LEVELS\C003L010.DAT LEVELS\C003L015.DAT LEVELS\C004L001.D2 LEVELS\C004L001.DAT LEVELS\C004L003.DAT LEVELS\C004L004.DAT LEVELS\C004L007.D1 LEVELS\C004L007.DAT LEVELS\C004L013.DAT LEVELS\C004L015.DAT LEVELS\C005L001.D1 LEVELS\C005L001.D2 LEVELS\C005L001.DAT LEVELS\C005L005.DAT LEVELS\C005L015.DAT LEVELS\C006L001.D1 LEVELS\C006L001.D2 LEVELS\C006L001.DAT LEVELS\C006L003.D1 LEVELS\C006L003.D2 LEVELS\C006L003.DAT LEVELS\C006L005.DAT LEVELS\C006L007.DAT LEVELS\C006L015.D3 LEVELS\C007L001.D1 LEVELS\C007L001.D2 LEVELS\C007L001.DAT LEVELS\C007L003.D1 LEVELS\C007L003.D2 LEVELS\C007L003.D3 LEVELS\C007L003.DAT LEVELS\C007L005.DAT LEVELS\C007L007.D1 LEVELS\C008L001.DAT LEVELS\C008L003.D1 LEVELS\C008L003.D2 LEVELS\C008L003.DAT LEVELS\C008L005.DAT LEVELS\C009L001.D1 LEVELS\C009L001.D2 LEVELS\C009L001.DAT LEVELS\C009L003.DAT LEVELS\C009L007.DAT LEVELS\C010L001.D1 LEVELS\C010L001.D2 LEVELS\C010L001.D3 LEVELS\C010L001.DAT LEVELS\C010L015.DAT LEVELS\C011L001.DAT LEVELS\C012L001.DAT LEVELS\C020L001.D1 LEVELS\C020L002.DAT LEVELS\C020L007.DAT LEVELS\C021L001.D2 LEVELS\C021L001.D3 LEVELS\C022L001.D1 LEVELS\C022L001.D2 LEVELS\C022L002.DAT LEVELS\C022L003.D2 LEVELS\C022L003.DAT LEVELS\C022L004.DAT LEVELS\C022L013.DAT LEVELS\C025L001.D1 LEVELS\C025L001.D3 LEVELS\C025L015.D3 LEVELS\C026L001.DAT LEVELS\C026L002.DAT LEVELS\C026L003.DAT LEVELS\C026L004.DAT LEVELS\C027L001.DAT LEVELS\C027L002.DAT LEVELS\C027L003.DAT LEVELS\C027L015.D3 LEVELS\C028L001.D2 LEVELS\C028L001.D3 LEVELS\C028L002.DAT LEVELS\C028L015.DAT LEVELS\C030L001.D1 LEVELS\C030L001.D2 LEVELS\C030L001.D3 LEVELS\C030L002.DAT LEVELS\C030L008.D1 LEVELS\C030L008.D2 LEVELS\C032L001.D1 LEVELS\C032L002.D1 LEVELS\C032L002.DAT LEVELS\C032L005.DAT LEVELS\C032L015.DAT LEVELS\C035L001.D1 LEVELS\C035L001.DAT LEVELS\C035L002.DAT LEVELS\C035L004.DAT LEVELS\C035L005.DAT LEVELS\C035L007.DAT LEVELS\C035L015.D3 LEVELS\C036L001.D3 LEVELS\C036L001.DAT LEVELS\C036L002.DAT LEVELS\C036L003.D2 LEVELS\C036L003.DAT LEVELS\C036L004.DAT LEVELS\C036L005.DAT LEVELS\C040L001.D1 LEVELS\C040L001.D2 LEVELS\C040L001.D3 LEVELS\C040L001.DAT LEVELS\C040L005.DAT LEVELS\C040L013.DAT LEVELS\C040L015.D1 LEVELS\C040L015.D2 LEVELS\C040L015.DAT LEVELS\C041L001.D1 LEVELS\C041L001.D2 LEVELS\C041L001.D3 LEVELS\C041L001.DAT LEVELS\C041L002.D1 LEVELS\C041L002.D2 LEVELS\C041L002.D3 LEVELS\C041L002.DAT LEVELS\C041L003.DAT LEVELS\C041L005.DAT LEVELS\C044L001.D1 LEVELS\C044L001.D2 LEVELS\C044L001.D3 LEVELS\C044L001.DAT LEVELS\C044L002.D1 LEVELS\C044L002.D2 LEVELS\C044L002.DAT LEVELS\C044L003.D1 LEVELS\C044L003.DAT LEVELS\C044L005.DAT LEVELS\C044L007.D1 LEVELS\C044L007.DAT LEVELS\C044L015.D1 LEVELS\C044L015.DAT LEVELS\C045L001.DAT LEVELS\C045L002.DAT LEVELS\C045L015.D3 LEVELS\C046L001.D1 LEVELS\C046L001.D2 LEVELS\C046L001.D3 LEVELS\C046L001.DAT LEVELS\C046L002.D2 LEVELS\C046L002.DAT LEVELS\C046L005.DAT LEVELS\C046L008.DAT LEVELS\C046L009.DAT LEVELS\C046L010.DAT LEVELS\C046L014.DAT LEVELS\C046L015.D1 LEVELS\C046L015.D2 LEVELS\C046L015.D3 LEVELS\C046L015.DAT LEVELS\C047L001.D1 LEVELS\C047L001.D2 LEVELS\C047L001.D3 LEVELS\C047L001.DAT LEVELS\C047L002.DAT LEVELS\C047L011.DAT LEVELS\C047L015.D1 LEVELS\C047L015.DAT LEVELS\C049L009.DAT LEVELS\C050L001.D1 LEVELS\C050L001.D2 LEVELS\C050L001.D3 LEVELS\C050L001.DAT LEVELS\C050L002.D1 LEVELS\C050L002.D2 LEVELS\C050L002.D3 LEVELS\C050L002.DAT LEVELS\C050L003.DAT LEVELS\C052L001.DAT LEVELS\C052L007.DAT LEVELS\C060L005.DAT LEVELS\C060L015.DAT LEVELS\C065L001.DAT LEVELS\C065L002.DAT LEVELS\C065L003.DAT LEVELS\C065L005.DAT LEVELS\C070L011.D1 LEVELS\C070L011.DAT LEVELS\C079L001.D2 LEVELS\C079L002.DAT LEVELS\C079L015.D3