It’s a bit weird, but DMG page 24 (though I'm talking 2014 here) specifies that generally an unwilling soul can’t be forced back into the body. So unless a spell specifies otherwise, this would not work.
Because of how this spell is worded, assuming the Lich got killed at least once while being a Lich means he'll be unable to be targeted by this either way because he was undead when he died.
I think that’s a big strength of tabletops too, but I sometimes wish people would adhere a bit more to the rules, because while some things are not covered by them, changing the things that are is a good way to get me to be very hesitant to do anything because I can’t rely on achieving anything close to the intended outcome if I can’t rely on the rules.
I’d say it’s quite clear by RAW that once your third death save-fail happens your very much dead-dead. The DM is allowed to change any RAW of course (as this is RAW too), but without those changes it's very much not arbitrary.
I think nonliving creatures may be more specific versions of objects then, since I couldn’t find any reference of creatures not being considered objects (because who would even say that, it should be obvious if you use your brain), but it also means that if a spell or ability only allows you to target or create objects and has no specification in regards to creatures, undead and constructs are valid targets by RAW.
The last one is actually covered by it I'd say, because (as by rules of spell targeting) you cannot see the blood and furthermore (as confirmed by "Water breathing" not working in wine) spells that affect water really only affect water and that’s it.
I know you mean it as a joke, but in my experience, punishing a player for trying to find out what you will and won’t allow them to do is a good way to get players that don’t want to be creative. Just tell them that you will not allow it. (Also… poor Mystra for having to waste that much divine power on someone trying to use spells in a way it can’t be used in anyway.)
If everyone at your table is habilitated fun, then… well, have fun, but I'd advise against it.
I mean… since the spell does not say that undead are excluded from revivification, you could very well just do that if you get your hands on the ghost in time.
I think limiting spells to mostly do what they say they do (while ignoring obviously stupid interactions like the one above) is actually somewhat balancing, because it otherwise increases the power and utility of casters over martials even further.
That one does not work RAW either way, because lungs are not an open container.
But I never said I wanted to actually exploit this in a game. You can’t really exploit this one even if you want to, because it’s bound to be extremely specific. I just wanted to point out the weirdness.
Okay. But do you actually allow any use of the spell that's not as originally intended? Because some things are technical applications of the rules which rely on rules working as intended but still in very specific way without breaking the game at all.
No I don’t want to play RAW. I just don’t want in game solutions to out of game problems. Just (and I know that this will seem extremely absurd, but hear me out!) talk to your players about it like a normal person and make it clear before you start to play.
It’s a bit weird, but DMG page 24 (though I'm talking 2014 here) specifies that generally an unwilling soul can’t be forced back into the body. So unless a spell specifies otherwise, this would not work.
Because of how this spell is worded, assuming the Lich got killed at least once while being a Lich means he'll be unable to be targeted by this either way because he was undead when he died.