Our warlock wants to use this with the book of shadows can he? Hes a lurker in the deep but I dont know who his patron is

Quick lookuf for the lurker shows that he will be able to cast Commune with Nature, slightly different spell :)

it is a ritual spell, so if your warlock has the Book of Ancient Shadows invocation + is a level 10 warlock + has a spell scroll for Commune, then yes he can use this spell.

well what i meant was if he casted it would he commune with his patron? it says you communicate with a divine proxy or deity 

The major point is "Rule 0" which states that the DM has the final say at each table and the rules are just guidelines/suggestions. If you are the DM and you want your group's Warlock to be able to cast commune, then you are allowed to make it so. You don't need anyone's special written permission to do so. If it fits your story/setting and it is what both you and the player(s) want, then absolutely allow it. Or, it is even possible to make a homebrew version special for your game and your Warlock and make a version that the Warlock's Patron gives to him so that they can communicate much easier. If the Patron is one that likes to chat and/or give their warlocks tasks, then giving the Warlock the ability to talk to them and keep them updated and such makes sense. For example, one of the warlocks I DM for has a patron that is obsessed with finding knowledge and uncovering secrets, it would be totally fitting that the patron gives the warlock the option to Commune with it whenever it has more knowledge to share. It makes sense and would be a fun gift for the patron to give to their warlock. Hope that helps.

I got that and it's fine we were just unsure whether he should it was a while ago but I think the dm allowed him... It wasn't as useful as he thought it was

If youre the gm you probably want to know who the patron of each character is before the campaign even starts

Quote from ralstonprime>>

The major point is "Rule 0" which states that the DM has the final say at each table and the rules are just guidelines/suggestions. If you are the DM and you want your group's Warlock to be able to cast commune, then you are allowed to make it so. You don't need anyone's special written permission to do so. If it fits your story/setting and it is what both you and the player(s) want, then absolutely allow it. Or, it is even possible to make a homebrew version special for your game and your Warlock and make a version that the Warlock's Patron gives to him so that they can communicate much easier. If the Patron is one that likes to chat and/or give their warlocks tasks, then giving the Warlock the ability to talk to them and keep them updated and such makes sense. For example, one of the warlocks I DM for has a patron that is obsessed with finding knowledge and uncovering secrets, it would be totally fitting that the patron gives the warlock the option to Commune with it whenever it has more knowledge to share. It makes sense and would be a fun gift for the patron to give to their warlock. Hope that helps.

Beyond 20

 

I find myself preparing this spell pretty much every day as a cleric. If it weren't a ritual I probably wouldn't as much, but the ability to ask a bunch of yes or no questions for free every day is just too nice to pass up.

“Incense and a vial of holy or unholy water”

What are some examples of this? Water from the river Stix? Urine? The bodily fluids of a fiend such as blood or saliva? The blood of an innocent man, ritually sacrificed? Water from a specific pool in some dark corner of the world? Water tainted by a Marilith? Water changed by an evil-aligned creature who casts Ceremony? Water stewed with an unholy herb? Some sort of fiendish Tea, Coffee, or lemonade? Water sourced from the lair of a Morkoth, Aboleth, or other great water creature? Water from a tainted water elemental?

Quote from DragonRiderHN >>

“Incense and a vial of holy or unholy water”

What are some examples of this? Water from the river Stix? Urine? The bodily fluids of a fiend such as blood or saliva? The blood of an innocent man, ritually sacrificed? Water from a specific pool in some dark corner of the world? Water tainted by a Marilith? Water changed by an evil-aligned creature who casts Ceremony? Water stewed with an unholy herb? Some sort of fiendish Tea, Coffee, or lemonade? Water sourced from the lair of a Morkoth, Aboleth, or other great water creature? Water from a tainted water elemental?

I always thought it was the same thing as holy water, but with powdered cast iron in it instead of silver. If it were ever to be used, I'd say it would deal 2d6 necrotic damage to fey and celestials. So basically, holy water but reversed so it's edgy and cool I suppose.

I know it's not intended this way but unholy water reads to me as regular water (or any water that isn't holy water).