You don't use the multiclass spellcasting rules
The multiclassing rule for the spellcasting feature (which gives you spell slots based on the Multiclassing Spellcaster: Spell slot table) because it only comes into effect:
you have the Spellcasting feature from more than one
class, use the rules below. If you multiclass but have the
If you look in the rules for multiclass spellcasting, it has a section dedicated to pact magic (which is what you have as a warlock)
Pact Magic. If you have both the Spellcasting class feature and the Pact Magic class feature from the warlock class, you can use the spell slots you gain from the Pact Magic feature to cast spells you know or have prepared ...
Your DM is correct in that you do not have level 3 spells, but you should have 5 level 1 spells and 3 level 2 spells. The 5 level 1's are the 4 from Cleric and 1 from Warlock.
Since Warlock's use Pact Magic and not Spellcasting, you do not use the multiclassing table. You simply add have your Cleric spell slots and your Warlock spell slots. Now, that being ...
They don’t interact or interfere with each other at all.
Before Natural Recovery (I.e. normally), your Pact Magic spell slots refresh on a short or long rest, and your Spellcasting spell slots refresh on a long rest only.
Once you get Natural Recovery, your Pact Magic spell slots still refresh on a short or long rest - nothing changes there - but your ...
Sort of, but not as well as you might like.
The first thing to understand is that Warlock Pact Magic doesn't stack with other kinds of casting. If you have a character who has 3 levels in druid, and 3 levels in cleric, they have the spell slots of a 6th level character. (Their spells known only go up to spell level 2, but they can upcast.) if you have ...
In short, yes.
All spellcasting classes apart from warlock have the Spellcasting feature
while warlocks get the pact magic feature -
The Warlock table shows how many spell slots you have to cast your warlock spells of 1st through 5th level. The table also shows what the level of those slots is; all of your spell slots are the same level. To cast one of ...
No; invocation prerequisites are based on warlock level.
Eldritch Invocations are based on your Warlock level, not your character level. Per the description (PHB, 110):
If an eldritch invocation has prerequisites, you must meet them to learn it. You can learn the invocation at the same time that you meet its prerequisites. A level prerequisite refers to ...
No you would not
Sculptor of Flesh
Prerequisite: 7th level
You can cast polymorph once using a warlock spell slot. You can’t do so again until you finish a long rest.
You would need to be at least a 7th level Warlock. The character level does not matter for the prerequisite.
As stated on PHB pg. 110
If an eldritch ...
Reading over the infusion and the description of firearms and that they have their own proficiency, it looks like the Repeating Shot is not able to be put on the firearm. The infusion has listed for its requirements, "Item: A simple or martial weapon with the ammunition property (requires attunement)". The problem here isn't with the ammunition property, but ...
The Reload property of the Firearms, while included in the Gunslinger's description, refers to items (weapons) and as such you could argue it's not part of the class itself.
The Artificer's infusion allows the creation of a magic item so you'd be effectively using a different item with different properties.
If you find that to be unbalanced, though, you ...
It's unclear if there’s any official answer, but likely works based on DM discretion.
UA generally isn't balanced for multiclassing, and Matt Mercer's stuff isn't canonical, so WotC wouldn't consider it when designing their own content, so there probably won't be a canonical answer for this from WotC.
That said, however, it would be reasonable for it to ...
Don't silo the animated dead
The animate dead spell's description, in part, says
No matter how many times you use this spell, however, you can control only 4 HD worth of undead creatures per caster level. If you exceed this number, all the newly created creatures fall under your control, and any excess undead from previous castings become uncontrolled. ...
To start, the key thing here is Caster level. This is a specific function of a character's levels in a specific spell casting class. Page 208 of the Core Rules states, under "Caster Level":
A spell's power often depends on its caster level, which for most spellcasting characters is equal to her class level in the class she's using to cast the spell.
Yes, it can make spell slots used by other classes.
No, it can not make a Warlock spell slot specifically.
Total spell slots from multiclassing are calculated using the method described on page 165 of the PHB (SRD reference):
You determine your available spell slots by adding together all your levels in the bard, cleric, druid, sorcerer, and wizard ...
Wizards cannot transcribe prepared spells from multiclassing
The "Your Spellbook" sidebar is clear that Wizards need to find a spell in a spellscroll or spellbook to transcribe it into their spellbook, then only exception given in the sidebar is for lost spellbooks:
If you lose your spellbook, you can use the same procedure to transcribe the spells that ...
Not directly, no
You can't scribe a prepared spell into a wizard's spellbook as the rules state you must copy the spell from a scroll:
Copying a Spell into the Book. When you find a wizard spell of 1st
level or higher, you can add it to your spellbook if it is of a spell
level you can prepare and if you can spare the time to decipher and
copy it. ...