Extended LVL
From ASSS Wiki
Extended .lvl Files, or eLVL files are a (relatively) new, reverse compatible format for representing maps in SubSpace/Continuum. That being said it is desirable to switch to the eLVL format as it may not stay reverse compatible forever (think arbitrary number of tile types). ASSS is currently the only server capable to make practical use of eLVL files.
They can be generated using a Python script available at the ASSS site, using Continuum Level / Ini Tool or DustEd.
A specification for the ELVL_Format is available on the wiki.
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