Thank you.

That was what I thought.

It would be nice if they actually stated that in the book.

It does say that in the description of greater invisibility

Quote from SDHshadow >>

So quick question about this spell. This spell states that anything that the target is carrying is also invisible and that if the TARGET attacks or casts a spell the effects end. So here is the question: If one was to cast invisibility on a horse wouldn't the people riding it also be invisible as they are being carried by the horse? Furthermore, because they aren't the target can't the riders of the horse be able to attack without the spell ending?

This is a bit of an old comment, but an important point.

That’s a very clever workaround, and a DM might just allow it, if argued well.

However, strictly Rules As Intended, I rule against it, and say you’d need something like find steed spell sharing effect.

Casting words are:

Librarium Invaldius

any advantages to attacking while invisible/in stealth?

DM might give you surprise and/or advantage first round.

One thing you could do is make yourself invisible and run around doing the help action. Help action doesn't make you visible again. :)

 Shouldn't this be available for the Arcane Trickster?

Quote from Ebon_Sky >>

any advantages to attacking while invisible/in stealth?

 See the invisible condition. You have advantage on attacks, attacks against you have disadvantage and you are considered heavily obscured for the purposes of hiding (and only hiding), meaning that you can hide anywhere without needing any other sort of cover.

Keep in mind: simply going invisible in the middle of combat does not stop creatures from knowing your location (as in, the square you are in) unless you actively use the stealth skill.

I know magic isn't bound by laws of physics, but, if the lenses & retinas of your eyes are invisible, doesn't this render the target (or you) blind?

Quote from SDHshadow >>

So quick question about this spell. This spell states that anything that the target is carrying is also invisible and that if the TARGET attacks or casts a spell the effects end. So here is the question: If one was to cast invisibility on a horse wouldn't the people riding it also be invisible as they are being carried by the horse? Furthermore, because they aren't the target can't the riders of the horse be able to attack without the spell ending?

 I'd say not.  The horse (or whatever) has a saddle or something, right?  The saddle would be invisible, but the rider wouldn't be. (Riding bareback, maybe...)  In general, I take "carried" to mean an object carried by a person (weapon, magic wand, so forth).

does it make u not be able to be Seen or just like a host were u can see them but not touch them?

favorite spell 

I can't find this spell for my bard in the creator?

If the creatures is hit, does it becomes visible?

Yes. But then the hostile creature could just make an attack to end the spell 

Charm Person + Greater/Invisibility is a lot of fun to mess with people. Charm them, then turn invisible and convince them you are a ghost. Or their ancestor.

yes

Invisibility + Malleable Illusions (Illusionist L6 feature): 

Change the target of your invisibility (touch range). Cast it at 3rd level and you can hit two targets - you and your friend are now invisible, but once they’re out of sight of the sentries you can go back and get someone else.

The invisible condition says that the creature's location can be detected by tracks it leaves. Does this mean that an invisible creature in the rain might be detected as raindrops bounce off of them?

Yes.

A thing a lot of folks seem to not realize about Invisibility in 5e: It really just lets you make your stealth rolls when you're in plain sight. And that's about it. Straight-up perception vs. stealth opposed check.

Mind you, as a DM I usually rule that if it's a sight-based check (Ex. hearing them during loud combat would be difficult) it's at a disadvantage.

But in a normal environment and they are moving? Or they are upwind and the creature has a good sense of smell?

Nope, just regular stealth checks v perception.