jtest is a map in the leaked Blood alpha. It is an earlier version of blood6/jcrypt, which itself is a prototype version of the final game’s E3M8: The Catacombs.
The map has a few differences when compared to blood6, including multiple ways from the starting area to the cylinder room (two of them were cut and turned into monster closets in blood6), earth axe zombies not coming from the ground due to using an incorrect tile (the same issue appears in the jcastle1 maps), a wrong tile for items in the right side’s connector room, no Hellhounds in the final room, and an incorrect texture for the sky.
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