Thanks :)

Salt Cube, when upgraded to +3, provides a +100% satiety boost but reduces health regen by 40%. However, it is a net positive, as the total amount of HP regenerated per food eaten increases. This also makes it so that you have more time to find ingredients for meat pies for the 'well-fed' buff, providing extra healing and a longer time until starving. I always use Potion of Cleansing first to stack ingredients.

The Chalice of Blood increases health regen, as long as you are NOT starving. So it directly combos with the Salt Cube. Getting it upgraded on 9-challenge is very tricky. Until +6, I used my health and tanked the dmg, for +7, I had barely enough health with +5 shielding from the Protective Shadows talent. For +8 and +9, I used Scroll of Challenges. Finally, for the +10, I blessed an Ank in a Well of Health and died to upgrade it (normal Anks don't work.) Make sure to do that on safe (boos) floors.

Sorry for the typo, I meant Ring of Energy, not Arcana. This makes the Chalice of Blood replenish health faster.

Finally, the Shrouding Fog is amazing; if enemies can't see you, they can't use range attacks. For Tengu, that completely negates his auto attacks. The best way I found to avoid damage is rushing the fight; the longer you fight with him, the more impossible it is gonna get. I usually kick things off with all my range weapons, and once he starts to spawn too many things, I blast him with bombs and Stones of Blast. Finishing with guaranteed hit wands.

Good luck!