Alchemy6.pk3 is a collection of selected maps which replace MAP01 to MAP09 of Doom 2.
Here are the authors of the nine maps:

MAP01-MAP09 (except MAP02) - Originally B79SOE.WAD by Berserker79, titled "Stranded on Erebus"+
MAP02 - Originally gzmarknight.WAD by Guy M. Babin, titled "The House That Sits in the Center"

+Converted from Doom to Doom 2.

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