Meld into Stone and its interaction

Question

As a feat for my Tempest Domain Cleric, I will pick Metamagic Adept (Distant Spell). Looking through spells that would benefit most from this feature, I became curious about Meld into Stone, as it seemed to me that this combination would make this spell more useful in many creative and fun ways (instead of being just a "hide and wait" or "rest safe" spell). But that bred quite a lot of questions, hopefully you can help.

1. Does it have to be stone or can it be any form of solid surface?
2. What happens if it's gravel? Does it count as multiple small objects or one surface? Same goes for sand which could be eroded rock.
3. Does it have to be solid stone all the way to contain you or should it be just the surface large enough for you to enter? Example - stone road is not exactly deep enough to contain human but it's surface is large enough for human.
4. What is visual of entering - is it like the stone is swallowing you slowly or, as the spell is instant, you are just entering stone as if you would move through opened door?
5. While in stone you can cast spells with target self - does it include scrolls?
6. Can you use your equipment abilities while in stone?
7. Ritual casting when moving - at which point you pick a target? At the end of the cast or it just fails if you have moved away? I would assume at the end.
8. "You can use your movement to leave the stone where you entered it, which ends the spell" - do you leave it to the same point you casted the spell from or just exit the stone, doesn't matter where it was moved in the meantime?
9. Can Distant Spell and Meld into Stone work together? - I believe it meets all criteria for this combo (distance: touch, so instead of touch just fill it out with "within 30 feet") but wanted to make sure if you agree.

Answer 1

You can combine Distant Spell with Meld into Stone

Meld into Stone has a range of "Touch" and says:

You step into a stone object or surface large enough to fully contain your body, melding yourself and all the equipment you carry with the stone for the duration. Using your movement, you step into the stone at a point you can touch.

The distant spell metamagic feature for Touch spells has this effect

When you cast a spell that has a range of touch, you can spend 1 sorcery point to make the range of the spell 30 feet.

This works straightforward for spells like bestow curse or cure wounds where your spell imposes an effect on the target that you touch. Instead of needing to touch them, you now can curse or cure them at a distance.

Normally with Meld into Stone, you simply can enter the wall at the point that you touched, usually right next to you. To walk in there, you have to use your movement.

All that changes with Distant Spell is that you now can pick a point up to 30 feet away as the point where you will be able to enter the wall. You still need to move to get there, and that means, you need to have enough movement for that. If you pick a wall 20 feet away and you have 30 movement, no problem (unless someone stops you). If you pick a wall 30 feet away, you either need 35 movement or more, like a wood elf, or you need to dash, or move again next round, or have some other way to shortcut the distance.

In all other respects, Meld into Stone remains unchanged.

As Thomas mentions some of your other questions have been answered here before. I can understand that you want to treat them together, but it might be worthwhile to ask the more tricky ones that have no ready answers again separately, to get a deeper analysis. Here is the short form:

1. Wall of fire: What's a 'solid surface' and what happens if it stops existing?
2. Wall of fire: What's a 'solid surface' and what happens if it stops existing?
3. It must be large enough to fully contain your body. A surface is 2D and cannot contain anything. The only sensible reading is that the stone must be large enough to fully contain your body. Since you meld with the stone, it must be made of stone.
4. The spell does not specifiy, so these flavor aspects are up to you and your DM.
5. It is highly unlikely that you can cast a spell from a scroll, as your body is fully surrounded by rock, so you cannot see anything, and you need to read a spell scroll to cast it. If you cannot see the scroll, you cannot read it. Maybe if you had some kind of X-ray vision. It is also not clear if you can move in general other than casting spells on your self. Spells only do what they say they do, and Meld into Stone only says you can cast spells on yourself and "You otherwise can't move.". So you would not be able to move to retrieve the scroll, or unroll it, to cast the spell if you do not already hold it open, too. [This one might be worth a separate question.]
6. Unlikely as "You otherwise can't move." which would preclude you from using any equipment. [This one might be worth a separate question.]
7. When is a spell cast? and At what point does a caster define the target of a spell?
8. "to leave the stone where you entered it" you entered it a point you can touch (or remote touched with your metamagic), not a point in space. That is where you leave it again. I'd say, if the stone somehow is moved, the point on the stone is also moved, and you leave it at that point whereever the stone then is. Also, if you interpret this as a point fixed in space, you'd leave at the space where you entered, but that would not make sense, as you and the stone are not there any more. (But on this one, doublecheck with your DM. [It also might be worth a separate question.]).
9. Yes, Distant Spell and Meld into Stone can work together. Casting it at a distance however might make it worse, not better, as it is easier to intercept you and stop you from entering the stone. Instead you could move to the wall, cast, and move in, with less risk and no wasted metamagic.

Answer 2

Does it have to be stone or can it be any form of solid surface?

You step into a stone object or surface

I read that as a stone object or a stone surface. I think the intent is perfectly clear, but a rules lawyer might argue there are two choices, one a stone object, the other a surface. I think even a lenient DM would not grant you that, but you could ask. I think it is very dubious though. I mean, it is called meld into stone, not meld into various things.

What happens if it's gravel? Does it count as multiple small objects or one surface? Same goes for sand which could be eroded rock.

You step into a stone object or surface large enough to fully contain your body

That means, a single stone object, large enough to fully contain your body. The DM could, of course, rule otherwise, and tell you that sure, you can meld into a "surface" comprised of sand, but to me the plain reading is a single solid stone object, at least large enough to hold you.

Does it have to be solid stone all the way to contain you or should it be just the surface large enough for you to enter? Example - stone road is not exactly deep enough to contain human but it's surface is large enough for human.

large enough to fully contain your body

That means, a single stone object, large enough to fully contain your body. See previous question.

What is visual of entering - is it like the stone is swallowing you slowly or, as the spell is instant, you are just entering stone as if you would move through opened door?

Well, you "step into [the stone object]". You're stepping into it. So I think your description of "move through opened door" is apt. Beyond that, it's not defined. The DM can narrate.

While in stone you can cast spells with target self - does it include scrolls?

You . . . can cast spells on yourself

The source of the spell you cast is not defined. As long as "you" are "casting a spell", I think it works, to include scrolls.

However, there's one huge problem: can you see? The spell says:

you can't see what occurs outside [the stone]

Whether you can see inside the stone is not defined, but it seems entirely reasonable that you cannot. It would have been clearer if the spell had said you were blind while within the rock, but it did not. However, it seems reasonable you can't see, since there's rock in front of your eyes. I mean, I guess there's rock in front of your eyes. You're magically "melded" into the rock, and that is not fully defined.

So, whether you can see to read a scroll is up to the DM, however, it's likely and reasonable that you can't see. If you can't see, you can't read a scroll.

Can you use your equipment abilities while in stone?

No. You can 1) cast spells on yourself 2) use your movement to leave the stone. "You otherwise can't move." Up for debate is whether you can even retrieve a scroll or material components. A lenient DM is likely not going to fret about details like that, but using any equipment seems off the table.

Ritual casting when moving - at which point you pick a target? At the end of the cast or it just fails if you have moved away? I would assume at the end.

This answer says "No explicit RAW, but evidence suggests target is selected when spell is released".

It seems reasonable that you cast the spell, then at the end you touch the stone. That seems reasonable, but really it's something the DM will need to narrate on a case-by-case basis. For instance, if you're thinking of some tricksy thing where you ritual cast it and then pick the target at the very last moment to some great mechanical advantage (I can't think what, but maybe you've come up with something clever), then as a DM I'm going to be looking at it with a skeptical eye.

"You can use your movement to leave the stone where you entered it, which ends the spell" - do you leave it to the same point you casted the spell from or just exit the stone, doesn't matter where it was moved in the meantime?

To me, the spell is written as if assuming the stone does not move in the meantime. To me, it would be strange if someone could move the stone, and then you pop out and you're back where you started, but the rules don't say.

As a DM I would rule that in general, your exit is probably relative to the stone. I'm a fan that there are some things characters need to learn in game. Edge cases here seem like that sort of thing.

Can Distant Spell and Meld into Stone work together? - I believe it meets all criteria for this combo (distance: touch, so instead of touch just fill it out with "within 30 feet") but wanted to make sure if you agree.

It looks to me like it would. A pretty interesting combination, but in the end, what does it really buy you? In combat, sure, you could jump into a stone over there, but then what? Misty step is cheaper and more versatile, and doesn't require metamagic. Out of combat, well, you can instead just . . . walk over to the stone.

This is going to be highly DM-dependent. Nobody the Hobgoblin says in their answer you'd need to use movement to move the 30 feet. That seems reasonable. It also seems reasonable that it would be a 30-foot teleport.

If the DM rules you need to move, why even bother with the metamagic? Just move and cast.

If the DM rules it's a 30-foot teleport, well, at least you can escape opportunity attacks that way. I don't even think that's all that overpowered for the cost of the metamagic specialization and the sorcery point. But then you're stuck in a rock. A knowing enemy could play all sorts of havoc then.