A cavern used for sacrifices most foul.

• difficult terrain at 4 of the 5 entrances/exits to slow down your players. remember -- caves are damp environments and rocky ground is often slick, to add a dexterous challenge.
• approach the altar from at least two points: stairs, which are exposed but easy to ascend. or, cliff-side, which is has more difficult terrain and a climb. however, players can hide and potentially sneak their way up.
• stalagmites create some cover for baddies and heroes.
• spooky ambiance, ooOOooh.

Hit me up for small changes (contact in profile). Feel free to clone and use. CC-BY.

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