His Majesty the Worm or Shadowdark?

Hi everyone. I’m going to my FLGS tomorrow and can’t decide between these two games! I already have OSR staples like S&W and OSE so I was thinking of something new to try like HMtW for mega dungeon goodness and to put my tarot cards to use, but I’ve heard a lot of good things about Shadowdark. Seems super popular.

The HMtW’s dungeon design course winning an Ennie drew my attention to the system.

Please help me decide, if you have any thoughts to share I would love to hear them!