While I think Warlock probably does need some major changes with the big move away from short rest limited uses in general*, I'm not happy at all with what they've done.

Warlocks are now half casters, but what they're replacing was really a pseudo full caster; okay so 5e warlock maxed out at four 5th-level slots, but if you could fit in two or three short rests that's actually a huge amount of high level spell casting (12-16 5th-level spells). Meanwhile they got almost the same number of 6th-level and higher slots as other casters thanks to mystic arcanum. Now they not only don't get mystic arcanum as standard, they get slower spell slot progression (don't get 5th-level spells until 17th-level), it's just too much to lose.

The compensation seems to be stronger pact boons to save an invocation on those (as some invocations are rolled into the boons now), but this still hardly balances for the big losses. So instead of eight invocations we get nine (or essentially 10), but to have mystic arcanum as we did before we need to spend four of those, plus a lot of useful spells we could previously get as invocations separately form mystic arcanums are now rolled into the mystic arcanums as well. In other words we've lost out on casting progression, invocations, and mystic arcanums all in one fell swoop; having more guaranteed slots is nice but it doesn't compensate for all of this in the slightest, and leaves the UA warlock worse off overall.

I dunno, this rethink needs a rethink IMO. Personally I think the move to long rest slots is fine in theory, but it's being handled all wrong; the warlock should get a custom progression. I'd like to see something like the following:

Basically the idea is that at each level you get 1 new spell slot at the highest level available to a full caster up until you hit 10th-level (two slots each at 1st-, 2nd-, 3rd-, 4th-, and 5th-level). From 11th-level onwards your lowest slot is promoted one level (or two if the next one up already has four slots) until you have only 3rd-, 4th-, and 5th-level slots. Finally at 19th and 20th levels you get one additional 3rd-level slot, bringing you to 12 total (four each of 3rd-, 4th- and 5th-level).

At the same time starting from 11th-level you gain access to the mystic arcanum invocation as proposed (but no longer applying to 1st to 5th-levels), enabling access to higher level "slots" with a total of four (one each of 6th-, 7th-, 8th- and 9th-level) for a total of up to 16 spells cast per long rest (ignoring at will invocations etc.).

The problem is this is way, way more complicated than pact magic was, just to make long rest casting scale better and in a way that's still unique to the warlock. I also have no idea how you'd handle multiclassing (maybe always handle the warlock last, applying the rules as give above but using combined caster level?).

*But this still feels like a lot of work when the real problem for 5e warlock casting is when people just don't take short rests enough; the better fix IMO is to drop short rests down to 15 minutes and give every class something that replenishes on a short rest, as we'd soon see short rests being taken way more often. D&D is loosely based on action hero mechanics after all, and you very rarely see action heroes take long breaks; they sit down, burn a wound closed with some gunpowder or staples, then they're right back to it at full effect, so this would make sense with that in mind.

Consider a simpler mechanic. 5E Warlocks have a fixed number of spell slots at a specific level. Rather than try to build a new and unique table, consider that One D&D Warlocks implement the variant spell points from the DMG: DMG Spell Point Variant. Employing spell points, invocations, and mystic arcanum provides a unique spell-casting experience. Warlocks might have fewer total spell points than an equal level Wizard or Sorcerer, but they recover them quickly.

To be honest, I'd like to see the full casters classes brought down to that spell slot progression.

I would suggest something like the following :

We use the warlock from the playtest as the base :
But remove the spell slots per level table and put the spell slots and slot level as they where for pact magic in the 2014 PHB
But unlike the 2014 PHB you do not regain these spell slots on a short rest. 


Instead you get the call on the pact  feature 
When you have to roll initiative you can quickly  remind the powers that grand you your pact magic about the pact they made.
You can chose to treat your initiative roll as a 1 and regain one of your expended spell slots granted by your pact magic feature.

The Mystic Arcanum Eldritch Invocation would changed to have a Prerequisite of 11th level and all references to lower levels removed from the table.

A new Eldritch Invocation would be added to give you the option to gain some lower level spell slots

Name Yet To Be Determined: 
Prerequisite: 5th-level Warlock or Higher
When you take this Eldritch Invocation you gain spell slots of the level for witch you a qualified, as shown on the table below.
You can use these slots to prepare any warlock spells you know but can not regain these slots using your call on the pact  feature.
Repeatable. You can take this invocation more than once. Each time you do so, the spell slots you gain must be of a different level. 

Warlock Level    :     spell slots gained
5th–6th                      2 1st level spell slots
7th–8th                      2 2nd level spell slots 
9th–10th                    2 3rd level spell slots
       

Need to throw in a small correction here. Other than bane, all the spells that used to be invocations are now just part of the warlock available spells. They were "rolled into" mystic arcanum because mystic arcanum gives you access to them at the same level as before with an invocation as before, but once you reach the level that your pact slots catch up they are just naturally available now, no invocation needed.

Many of these rants read like people have read the changes, but haven't built a character side by side and played yet.

You can see my original reaction on the second page of first impressions. So you know I had to come around to this. Try it, actually try it. Level 3 (bad needs help) level 5, level 9, level 13. The capstone hex master SUCKS. There is work that needs being done yes, but it is more consistent across different tables and that is a good thing. 

Is there maybe a way to do it elsewise, maybe. But this isn't the big loss that is being presented here.

Quote from Aquilontune >>

The capstone hex master SUCKS.

I actually thought that stacked up okay; at-will hex basically means that unless you need your bonus action for something else you have a permanent 3d6 extra damage per turn and disadvantage on target's ability checks of one type (which you could change continually if you want to). It's tough when Hex Master is being compared to Arcane Apotheosis which is an insanely powerful capstone on the Sorcerer (definitely OP).

Hex Master could probably use a sweetener though, it'd be interesting to see it tie into the pact boon, or coincide with a final boon improvement?

You make fair points on the mystic arcanums replacing invocation spells, but I still don't like the slot scaling at all; before we got 5th-level slots at the same time as any other full caster, but could recover them on short rest, now we're getting only as many 5th-level "slots" as we are willing to spend our invocations on until we finally get a proper one at 17th-level. I'm sure loads of people did complain about the small number of pact slots being on short rest recovery, but half caster is not a great alternative; as others have pointed out, what is the other half on warlock? Paladin/Ranger are half caster, half martial (fighter mostly) but what's the warlock split between? It's like half caster, half tiny bit of full caster, it's very strange.

Again though, like I and some others have said, the change from short rest pact slots is essentially solving the wrong problem; the problem is campaigns don't use short rests, but if they were encouraged to, warlocks (and monks, and others with short rest abilities) wouldn't have so much trouble. But I'm guessing that ship sailed back when they gave Dragonborn multiple breath attacks per long rest. Does feel like they solved the wrong thing though.

But another separate issue is we're also missing some of my favourite invocations; cloak of flies (could have been improved), eldritch mind (got rolled into hexer instead), maddening hex, relentless hex (needs to be usable at the same time you cast hex or change its target), tomb of levistus.

Quote from Aquilontune >>

Is there maybe a way to do it elsewise, maybe. But this isn't the big loss that is being presented here.

 I generally agree, in terms of overall power I think One D&D and 5e is roughly the same. Though the type of power / builds is very different. I'm still disappointed they went this way b/c I found the 5e warlock playstyle more interesting than this because of its unique strengths and weaknesses, but the One D&D warlock is completely viable as a character as presented here, it's certainly miles above druid, and better off than bard.

Quote from Agilemind >>

Quote from Aquilontune >>

Is there maybe a way to do it elsewise, maybe. But this isn't the big loss that is being presented here.

 I generally agree, in terms of overall power I think One D&D and 5e is roughly the same. Though the type of power / builds is very different. I'm still disappointed they went this way b/c I found the 5e warlock playstyle more interesting than this because of its unique strengths and weaknesses, but the One D&D warlock is completely viable as a character as presented here, it's certainly miles above druid, and better off than bard.

 I am not convinced it is the same power. There are a few bits that do boost it. POTB is pretty good and some invocations are nice. But it really doesn’t feel as strong. 

But the main thing for me is this just… isn’t Fun. It feels like I am playing a ranger with sprinkles on it and that’s not what I was signing up for here. The flavour overall is off. The power scaling doesn’t actually fit the class lore. It doesn’t feel as satisfying to me. I LOVE warlock and have played a tonne of them. But… if this change comes out I just don’t have any interest. Even if it ends up stronger overall (which I am very skeptics on) I would take the previous all day long with a simple boost to pact slots. 

Quote from Haravikk >>

Quote from Aquilontune >>

The capstone hex master SUCKS.

I actually thought that stacked up okay; at-will hex basically means that unless you need your bonus action for something else you have a permanent 3d6 extra damage per turn and disadvantage on target's ability checks of one type (which you could change continually if you want to). It's tough when Hex Master is being compared to Arcane Apotheosis which is an insanely powerful capstone on the Sorcerer (definitely OP).

Hex Master could probably use a sweetener though, it'd be interesting to see it tie into the pact boon, or coincide with a final boon improvement?

You make fair points on the mystic arcanums replacing invocation spells, but I still don't like the slot scaling at all; before we got 5th-level slots at the same time as any other full caster, but could recover them on short rest, now we're getting only as many 5th-level "slots" as we are willing to spend our invocations on until we finally get a proper one at 17th-level. I'm sure loads of people did complain about the small number of pact slots being on short rest recovery, but half caster is not a great alternative; as others have pointed out, what is the other half on warlock? Paladin/Ranger are half caster, half martial (fighter mostly) but what's the warlock split between? It's like half caster, half tiny bit of full caster, it's very strange.

Again though, like I and some others have said, the change from short rest pact slots is essentially solving the wrong problem; the problem is campaigns don't use short rests, but if they were encouraged to, warlocks (and monks, and others with short rest abilities) wouldn't have so much trouble. But I'm guessing that ship sailed back when they gave Dragonborn multiple breath attacks per long rest. Does feel like they solved the wrong thing though.

But another separate issue is we're also missing some of my favourite invocations; cloak of flies (could have been improved), eldritch mind (got rolled into hexer instead), maddening hex, relentless hex (needs to be usable at the same time you cast hex or change its target), tomb of levistus.

 You don't get 3d6 hex off of hex master. Anytime an ability allows you to cast a spell without expending a spell slot you cast it at its base level. And you still have to waste your concentration on it. Hex master is garbage. 

Also your invocations can only ever get you one 5th level slot and one 4th, one 3rd...so on and so forth. 

I get the primary complaint. I encourage people to actually try it. It isn't perfect, it is more consistent at tables because of how people treated short rests. 

Remember a big part of this update is about updating things to match how the game is played today. Their pockets say people are happy playing the way they are, not the way wizards intended. So they are trying to change things to work with how tables play it.

Tables are inconsistent with short rests, so they are changing classes to work with the intended power and fantasy no matter the table.

Quote from Agilemind >>

To be honest, I'd like to see the full casters classes brought down to that spell slot progression.

My observation here isn't new: The number of spell slots characters get in the 2014 rules was based on a set of assumptions about play patterns (in short: that dungeon crawling is the norm) that aren't true for most groups. The writers have known about this discrepancy for a long time now, but if they change it, they're "nerfing" all casters, and that doesn't sell books.

I don't think we're likely to ever see the default spell slots get reduced in this edition's lifetime. At best, we might get a blurb about a variant rule, and they'll probably call it something overly dramatic like they did with "gritty realism." Let's say, "deadly magic shortage that ruins everything, and that you should only pick if you're an insane masochist, because it's like the Dark Souls of D&D, except way worse because despite the memes, Dark Souls actually goes out of its way to make the difficulty curve engaging and humorous, and provide you with community tools like multiplayer and notes to ease the challenge and affect a recurring theme of jolly cooperation in an otherwise hopeless setting, whereas this variant rule will simply salt your crops and spoil your reputation, and you'll be miserable the whole time, and get cancelled on social media, and stub your toe."

If I'm allowed to dream big, and I mean, who's going to stop me, then I'd like to imagine all the classes come with variants inside the PHB for fitting them into different types of campaigns. Imagine if they had rules for "grim and gritty Fighters" (reduced HP; equipment damage) vs "superhero action Fighters" (healing surges; instead of loot including magic weapons, it includes magic gems for your chosen signature weapons). Just take the variant rules (update them a little), and move them to a place where players can know what they're getting into while they make their characters. I think that's a good idea, though I do say so myself.

Anyway.

Quote from Haravikk>>

Quote from Aquilontune>>

Snip

What is the other half on warlock? Paladin/Ranger are half caster, half martial (fighter mostly) but what's the warlock split between? It's like half caster, half tiny bit of full caster, it's very strange.

Conceptually, I feel like half-Expert would make sense. And there are a couple of features which lean that way. Lessons of the Ancient Ones, Eyes of the Rune Keeper. That might be all lol. In practice, right now, it doesn't feel like it's half-Expert. But it could. Would anyone like that, though? That's how the Bard was in earlier editions. And it might have been the least popular class in the PHB back then.

Quote from Aquilontune >>

 

You don't get 3d6 hex off of hex master. Anytime an ability allows you to cast a spell without expending a spell slot you cast it at its base level. And you still have to waste your concentration on it. Hex master is garbage. 

Also your invocations can only ever get you one 5th level slot and one 4th, one 3rd...so on and so forth. 

 Anytime an ability lets you cast a spell without expending a spell slot, it specifies at which spell level you cast it. Otherwise, I would assume you can cast it at whatever level you like, at least that's the obvious intent. Though it still sucks, I can agree on that. It shouldn't require concentration, at least for warlock.

Also, you can change the spell of Mystic Arcanum every time you level up. Two MA slots pretty much emulate pact magic.

Quote from kamchatmonk >>

Quote from Aquilontune >>

 

You don't get 3d6 hex off of hex master. Anytime an ability allows you to cast a spell without expending a spell slot you cast it at its base level. And you still have to waste your concentration on it. Hex master is garbage. 

Also your invocations can only ever get you one 5th level slot and one 4th, one 3rd...so on and so forth. 

 Anytime an ability lets you cast a spell without expending a spell slot, it specifies at which spell level you cast it. Otherwise, I would assume you can cast it at whatever level you like, at least that's the obvious intent. Though it still sucks, I can agree on that. It shouldn't require concentration, at least for warlock.

Also, you can change the spell of Mystic Arcanum every time you level up. Two MA slots pretty much emulate pact magic.

 That is not how rules as written currently works OR rules as intended has been.

If it did the new patron abilities that say " you can cast one of the spells from your patron list without using a spell slot" at third level would allow me to cast burning hands as a 9th level spell at level 3. Obviously can't do that.

ALL abilities that say you can cast a spell without consuming a spell slot cast the spell at its base level, not whatever level you want. If it did you could upcast your mystic arcanum to what ever level you want.

Quote from Aquilontune >>

 

That is not how rules as written currently works OR rules as intended has been.

If it did the new patron abilities that say " you can cast one of the spells from your patron list without using a spell slot" at third level would allow me to cast burning hands as a 9th level spell at level 3. Obviously can't do that.

ALL abilities that say you can cast a spell without consuming a spell slot cast the spell at its base level, not whatever level you want. If it did you could upcast your mystic arcanum to what ever level you want.

 Obviously, you can't cast a spell with a spell slot of a level that you don't have. I don't see a problem with free casting of Burning Hands as a 3rd level spell once per day if you have access to 3rd level slots. It doesn't break anything. You could cast Fireball for free with the same feature by then anyway. Wizard's Spell Mastery feature explicitly states, "You can cast those spells at their lowest level without expending a Spell Slot when you have them prepared. If you want to cast either spell at a higher level, you must expend a Spell Slot as normal". Explain to me why warlock's Spellcasting feature or Hex Master feature don't have the same text.

Quote from kamchatmonk >>

Quote from Aquilontune >>

 

You don't get 3d6 hex off of hex master. Anytime an ability allows you to cast a spell without expending a spell slot you cast it at its base level. And you still have to waste your concentration on it. Hex master is garbage. 

Also your invocations can only ever get you one 5th level slot and one 4th, one 3rd...so on and so forth. 

 Anytime an ability lets you cast a spell without expending a spell slot, it specifies at which spell level you cast it. Otherwise, I would assume you can cast it at whatever level you like, at least that's the obvious intent. Though it still sucks, I can agree on that. It shouldn't require concentration, at least for warlock.

Also, you can change the spell of Mystic Arcanum every time you level up. Two MA slots pretty much emulate pact magic.

 They emulate Pact Magic if you play at some awful bizzaro table that doesn't do short rests, sure. You have far fewer options in this strange emulation as well - just the one option per spell level.

Quote from kamchatmonk >>

Quote from Aquilontune >>

 

That is not how rules as written currently works OR rules as intended has been.

If it did the new patron abilities that say " you can cast one of the spells from your patron list without using a spell slot" at third level would allow me to cast burning hands as a 9th level spell at level 3. Obviously can't do that.

ALL abilities that say you can cast a spell without consuming a spell slot cast the spell at its base level, not whatever level you want. If it did you could upcast your mystic arcanum to what ever level you want.

 Obviously, you can't cast a spell with a spell slot of a level that you don't have. I don't see a problem with free casting of Burning Hands as a 3rd level spell once per day if you have access to 3rd level slots. It doesn't break anything. You could cast Fireball for free with the same feature by then anyway. Wizard's Spell Mastery feature explicitly states, "You can cast those spells at their lowest level without expending a Spell Slot when you have them prepared. If you want to cast either spell at a higher level, you must expend a Spell Slot as normal". Explain to me why warlock's Spellcasting feature or Hex Master feature don't have the same text.

Because the game designers are not consistent in writing. And will come back later and tell you the intent is the raw.  Take devils sight, it specifies you can see in magical darkness with it.  Do you know what else can see in magical dankness, standard dark vision.  Standard dark vision just can't see in the magical darkness or a darkness spell. So devils sight supposedly is now the ability to see through the darkness spell not just magical darkness but no where does it tell you that, just that it can see in magical darkness which apparently dark vision can as well. Quirkily enough that kind of makes sense for the warlocks devils sight as its not dark vision, but an actual devils dark sight, is dark vision with the devils sight enhancement that says magical darkness does not impede its vision. Which apparently is meaningless as normal dark vision does that. So maybe devils dark vision is blocked by the spell who knows. none of it makes sense.

So to answer where does it tell you that, likely no where.  They probably made it up.(not Aquilontune, I'm talking about sage advice)

Quote from Haravikk >>

While I think Warlock probably does need some major changes with the big move away from short rest limited uses in general*, I'm not happy at all with what they've done.

Warlocks are now half casters, but what they're replacing was really a pseudo full caster; okay so 5e warlock maxed out at four 5th-level slots, but if you could fit in two or three short rests that's actually a huge amount of high level spell casting (12-16 5th-level spells). Meanwhile they got almost the same number of 6th-level and higher slots as other casters thanks to mystic arcanum. Now they not only don't get mystic arcanum as standard, they get slower spell slot progression (don't get 5th-level spells until 17th-level), it's just too much to lose.

The compensation seems to be stronger pact boons to save an invocation on those (as some invocations are rolled into the boons now), but this still hardly balances for the big losses. So instead of eight invocations we get nine (or essentially 10), but to have mystic arcanum as we did before we need to spend four of those, plus a lot of useful spells we could previously get as invocations separately form mystic arcanums are now rolled into the mystic arcanums as well. In other words we've lost out on casting progression, invocations, and mystic arcanums all in one fell swoop; having more guaranteed slots is nice but it doesn't compensate for all of this in the slightest, and leaves the UA warlock worse off overall.

I dunno, this rethink needs a rethink IMO. Personally I think the move to long rest slots is fine in theory, but it's being handled all wrong; the warlock should get a custom progression. I'd like to see something like the following:

Character/Spell Level	1st	2nd	3rd	4th	5th	Mystic Arcanum	Total
1st-level	1						1
2nd-level	2						2
3rd-level	2	1					3
4th-level	2	2					4
5th-level	2	2	1				5
6th-level	2	2	2				6
7th-level	2	2	2	1			7
8th-level	2	2	2	2			8
9th-level	2	2	2	2	1		9
10th-level	2	2	2	2	2		10
11th-level	1	3	2	2	2	6th-level	10 (+1)
12th-level		4	2	2	2	6th-level	10 (+1)
13th-level		3	3	2	2	7th-level	10 (+2)
14th-level		2	4	2	2	7th-level	10 (+2)
15th-level		1	4	3	2	8th-level	10 (+3)
16th-level			4	4	2	8th-level	10 (+3)
17th-level			3	4	3	9th-level	10 (+4)
18th-level			2	4	4	9th-level	10 (+4)
19th-level			3	4	4	9th-level	11 (+4)
20th-level			4	4	4	9th-level	12 (+4)

Basically the idea is that at each level you get 1 new spell slot at the highest level available to a full caster up until you hit 10th-level (two slots each at 1st-, 2nd-, 3rd-, 4th-, and 5th-level). From 11th-level onwards your lowest slot is promoted one level (or two if the next one up already has four slots) until you have only 3rd-, 4th-, and 5th-level slots. Finally at 19th and 20th levels you get one additional 3rd-level slot, bringing you to 12 total (four each of 3rd-, 4th- and 5th-level).

At the same time starting from 11th-level you gain access to the mystic arcanum invocation as proposed (but no longer applying to 1st to 5th-levels), enabling access to higher level "slots" with a total of four (one each of 6th-, 7th-, 8th- and 9th-level) for a total of up to 16 spells cast per long rest (ignoring at will invocations etc.).

The problem is this is way, way more complicated than pact magic was, just to make long rest casting scale better and in a way that's still unique to the warlock. I also have no idea how you'd handle multiclassing (maybe always handle the warlock last, applying the rules as give above but using combined caster level?).

*But this still feels like a lot of work when the real problem for 5e warlock casting is when people just don't take short rests enough; the better fix IMO is to drop short rests down to 15 minutes and give every class something that replenishes on a short rest, as we'd soon see short rests being taken way more often. D&D is loosely based on action hero mechanics after all, and you very rarely see action heroes take long breaks; they sit down, burn a wound closed with some gunpowder or staples, then they're right back to it at full effect, so this would make sense with that in mind.

I like your idea, but even so I think it should move a little more away from the low level spell slots, which is a good part of the invocations, and to a lesser extent feats and/or spells by the species, should cover it. and I also don't think short rest should be taken out of the equation, just lessen its impact: That it restore half of the highest level warlock points, rounded down (minimum 1).

I propose the following modification to your table:

This way it's more like 5e, few spell slots, but powerful, and less reliance on short rests, but still taking advantage in that mechanic, like the wizard.

And for multiclass, that provides slots like 2/3 spellcaster.

and about the duration of the short breaks, I think it should be 20 or 30 minutes, I prefer the 2nd, the emergency bandage and partial restoration of your mechanics should not be as express as 5-10 minutes, but it should not take 1 hour either .

Quote from kamchatmonk >>

Quote from Aquilontune >>

 

That is not how rules as written currently works OR rules as intended has been.

If it did the new patron abilities that say " you can cast one of the spells from your patron list without using a spell slot" at third level would allow me to cast burning hands as a 9th level spell at level 3. Obviously can't do that.

ALL abilities that say you can cast a spell without consuming a spell slot cast the spell at its base level, not whatever level you want. If it did you could upcast your mystic arcanum to what ever level you want.

 Obviously, you can't cast a spell with a spell slot of a level that you don't have. I don't see a problem with free casting of Burning Hands as a 3rd level spell once per day if you have access to 3rd level slots. It doesn't break anything. You could cast Fireball for free with the same feature by then anyway. Wizard's Spell Mastery feature explicitly states, "You can cast those spells at their lowest level without expending a Spell Slot when you have them prepared. If you want to cast either spell at a higher level, you must expend a Spell Slot as normal". Explain to me why warlock's Spellcasting feature or Hex Master feature don't have the same text.

 You are using the logic "it doesn't say I can't therefore I can". Your "obviously you cant upcast it beyond the spell slots you have available" isn't obvious, because just like the rules don't say you can't upcast your at will spells it also doesn't say you cant upcast past the point of the spell slots you have access to. So if you can use hex master to cast hex as a 5th level spell then I can use mystic arcanum to take bestow curse and cast it as a 9th level once a day at level 5. No lie sounds like a lot of fun and broken, but it isn't RAW or RAI it is TRDSIC.

To answer the question of why it is written into the wizard ability. It is basically reminder text for clarity. The wizard is getting this effect late in their career so it is just there for clarity on how it is supposed to work. The lock on the other hand has been using the mechanic since level 2. Remember they also make magic the gathering, reminder text is very common.

Quote from kamchatmonk >>

Quote from Aquilontune >>

 

You don't get 3d6 hex off of hex master. Anytime an ability allows you to cast a spell without expending a spell slot you cast it at its base level. And you still have to waste your concentration on it. Hex master is garbage. 

Also your invocations can only ever get you one 5th level slot and one 4th, one 3rd...so on and so forth. 

 Anytime an ability lets you cast a spell without expending a spell slot, it specifies at which spell level you cast it. Otherwise, I would assume you can cast it at whatever level you like, at least that's the obvious intent. Though it still sucks, I can agree on that. It shouldn't require concentration, at least for warlock.

Also, you can change the spell of Mystic Arcanum every time you level up. Two MA slots pretty much emulate pact magic.

Sure, if it specifies the level then you use that (e.g. Shepherd Druid's Faithful Summons ability.)  However, the official rule is that if the ability doesn't specify a level, you must use the minimum. That's why the UA Warlock capstone is currently so bad, because they seemingly forgot this rule.

Here is the relevant Sage Advice:

What level is a spell if you cast it without a spell slot?

Such a spell is cast at its lowest possible level, which is the level that appears near the top of its description. Unless you have a special ability that says otherwise, the only way to increase the level of a spell is to expend a higher-level spell slot when you cast it.

Here are some examples:

• The warlock’s Chains of Carceri feature lets a warlock cast hold monster without using a spell slot. That casting of hold monster is, therefore, 5th level, which is the lowest possible level for that spell.
• The warlock’s Thief of Five Fates feature lets a warlock cast bane using a spell slot, which means the spell is 1st level or higher, depending on the slot that the warlock expends to cast it.
• The monk’s Disciple of the Elements feature lets the monk spend ki points, rather than a spell slot, to increase the level of a spell.

This rule is true for player characters and monsters alike, which is why the innate spellcasters in the Monster Manual must cast an innate spell at its lowest possible level.

My only issue is level 1, 2 and 3. I think you could start them with 2 first at 1,

So it would look like this.

1 (2 first)

2 (4 first)

3 (4 first, one second)

4 (4 first, 2 second)

5 (4 first, 2 second, 1 3rd)

6 (4,2,2)

7 (4,2,2,1)

8 (4,2,2,2)

9 (4,2,2,2,1)

10 (4,2,2,2,2)

11 (3,3,2,2,2)

12 (2,4,2,2,2)

13(1,4,3,2,2)

14 (0,4,4,2,2)

15 (0,3,4,3,2)

16 (0,2,4,4,2)

17 (0,1,4,4,3)

18 (0,0,4,4,4)

19 (0,0,4,4,4,1 6th)

20 (0,0,4,4,4,1 6th, 1 7th)

Meaning you are effectively getting your second 6th and second 7th with everyone else.

Quote from Aquilontune >>

 

You are using the logic "it doesn't say I can't therefore I can". Your "obviously you cant upcast it beyond the spell slots you have available" isn't obvious, because just like the rules don't say you can't upcast your at will spells it also doesn't say you cant upcast past the point of the spell slots you have access to. So if you can use hex master to cast hex as a 5th level spell then I can use mystic arcanum to take bestow curse and cast it as a 9th level once a day at level 5. No lie sounds like a lot of fun and broken, but it isn't RAW or RAI it is TRDSIC.

To answer the question of why it is written into the wizard ability. It is basically reminder text for clarity. The wizard is getting this effect late in their career so it is just there for clarity on how it is supposed to work. The lock on the other hand has been using the mechanic since level 2. Remember they also make magic the gathering, reminder text is very common.

 Mystic Arcanum does have the line "choose one spell from the Arcane spell list that has a level for which you qualify". By limiting the spell to the lowest level, you do nothing but limit the choices from 10 spells to 2. I'm not sure that's the intent. And I really doubt that they'd make a free 1st level spell a capstone feature, because that's a thing that 2nd level invocations do.

Anyhow, I agree that the wording needs work and clarifications. We need to put that into the survey.