I've specifically focused on means that don't require a spell slot to use. Left familiar as an exception because people like to have them anyway and it can be ritual cast.

RAW/RAI?

Rules as written, rules as intended.

The humble cone of cold:


Nope 

Nope 

Crawford also rules that See Invisibility doesn't remove the advantage/disadvantage on attack rolls because it doesn't say so in the spell's effect, so... Yeah, I always ignore what he says.

Ope great catch

By that logic you can see air because there's clouds in the sky.

Son of a bitch, that's a good argument.

Oh that's just bullshit

Technically it only refers to visible creatures. Objects doesnt have the adjective visible. Unlikely, but a particularly bull headed person could read this as though detect magic could identify invisible objects.

If you can target an invisible wall, it introduces a lot of ways for things to go wrong. The spell caster is taking elements on faith and making assumptions, and those can be subverted...

I would go line of fire logic. You theoretically can not target the wall, but you can target something on the outerside and will then hit the wall instead

I'm kinda surprised how vague many of the DnD rules are written. Didn't they have a rules lawyer at hand when writing these?

As I have said in another comment, that is RAW not what would happen: "You can’t even cast it on something behind the wall, because you cannot target something (or someone) with a spell if they are behind total cover. Total cover is created by being behind completely behind an obstacle (like a wall). This counts even if the obstacle is invisible." Furthermore, because if you chose an invalid target for a spell, you’d still expend the spellslot but there would be no effect. So you actually spend a sixth level spell a lot to achieve nothing." It’s very much not RAI I'd say and I would likely handle exactly like you described, but the RAW was so wonky that I wanted to make the meme when I found out about it.

Yeah I thought of that one as well. It’s one of those weird cases of imprecise wording.

I actually think it’s a fair restriction for spells that require sight. It imposes a somewhat interesting limit on casters, especially since a lot of spells still do something on a miss.

Funnily enough, Shatter actually has a very easy solution: Objects just take the damage and that’s it.