Twilight Warrior Base Class (with alternative casting system) [PEACH]

[Ze_Azrael]

Hey zeek0,
I stumbled upon this earlier today and I gotta say I absolutely love the concept. The astral theme and the energy toggling mechanic are just plain awesome.
I realize I'm not looking at the most updated version, but I'm still gonna give some feedback in no particular order. I apologize if this feels all over the place, or too critical. My intention is to be constructive.
Also I apologize for the incoming wall of text. The TLDR would be I agree with Dean in that it's a tad weak, the wonderful flavor and mechanics could be amped up, and I'm spoiled and can't wait for things.

So I'm a fan of the Energy toggling mechanic. I like that the class is a half-caster, it feels perfect for a class whose theme is heavy on halves and balance. However I feel it is used perhaps too sparingly. Sure, it interacts with your spell-casting, determining which spells you can cast at any given time and forcing you to plan ahead by converting energy, but besides casting there's little that interacts with Energy. There's the two first level features I'll talk about later, and the 7th level (Lunar) feature. That's it. I feel this is a missed opportunity.
Since the class is partly modeled after the Warlock, I'd like to point out that in order to compensate for their limited amount of available slots, Warlocks have a fair amount of good at-will options: EB, Invocations, and pretty much all their patron features are either passive or 1/short rest.
I'm intrigued to see what you do with the cantrips, as this might already address this, but I think having more (non-Incantation) options that interact with Energy would be beneficial not only mechanically, but to truly highlight it's theme of balancing extremes.

Besides the awesome energy toggling mechanic, there's something odd about the TW casting. You want it to be a half-caster, but with the resource management of a warlock, where they regain slots per short rest. I won't get into the debate of table dependency, party makeup, etc, and will assume that the principles the PHB is designed around are the goal we are trying to achieve for balancing this class.
With this in mind, and just as a baseline comparison, the TW should have 1 slot from levels 2-6, 2 slots from levels 7-16, and 3 slots from levels 17-20. I can show you the math (couldn't figure out how to make a nice table here) but basically what I did was, at any given level, convert the Ranger/Paladin's slots into spell-points, then divided that by the spell-point cost of their highest available slot, and divide that by 3 (since 2 short rest per day). This should give you the number of equivalent warlock slots.

Now there's a couple problems with this. First and foremost is that the TW doesn't quite function the same as a Warlock: they don't automatically cast a spell at their highest available level. They certainly could but they have the additional requirement of needing to use all their Energy (and thus needing it to all be of the same type). And of course having a single slot until level 7 just isn't fun.
I'm honestly not sure how to go about this and would suggest you rethink this (or explain it so I understand your intent), as it feels rather awkward giving it almost identical slot progression as the Warlock, while having the option to 'waste' a whole slot by using only 1 point instead of 5, and being a half-caster.

I had a question regarding Celestial Energy. It says that whenever you gain a point you decide if it starts Solar or Lunar. Does this mean that if say I choose 2 Lunar, 3 Solar, they reset to this configuration at the end of a Long Rest? Do they reset at all? Or is it only at the very start of a level and then they just toggle as they're used?

Solar Weapon just doesn't seem to do anything, in fact it seems to be a tax, forcing an Energy toggle every time you want to attack... When you want to toggle it then it's certainly very nice and convenient, but when you want to build up your Solar Energy then you're forced to either forego attacking, or use a plain old iron-and-wood weapon. Neither of these options seem very cool to me to be honest... Besides that, the only benefit is the BA summoning and free ammo.. it doesn't bypass resistances or anything... heck it doesn't even glow...

In contrast, Lunar Shield seems quite strong. It allows you to don a shield as a Reaction as opposed to an Action, doff it for free, and gain +1 AC or give it to an ally as a bonus action. Since you can't do this and do an Incantation, and this is one of the class' two Bonus Actions, it means you'll want to spam this whenever you would take the Attack action.
As you pointed out, using this and Attacking leaves your Energy pool the same. This means you can't reliably accrue Solar Energy. Unless this is your intention (or your intention is to rely on the Path feature to gain energy), I would strongly suggest changing this.
Spending a point for Lunar Shield is an "optional" beneficial feature. You gain something when you use it, but you don't need to use it. And even if you don't spend it, you still gain the benefit of an action-economy breaking shield, which is great.
Solar Weapon is not. You lose something if you don't use it.

I would suggest adding a similar "optional" beneficial feature to Solar Weapon. Something that you want to use every turn because it's cool, but you can forego for the sake of Energy management and not feel like you're getting shimmed. I propose something like dealing an extra 1d4 fire damage when you spend a point.

This makes the class fairly front loaded though, as I think each feature is a little better than a fighting style (so in a way you get Defense, Protection, and Dueling) which would probably be a problem for multiclassing, especially since they'd stack... I personally don't care much about this for the same reason I don't care much about capstone features. I never play at level 20 and if I'm gonna play a homebrew class is because it fits a concept better than any of the standard options, not to game the system with unintended interactions. But it's worth mentioning I suppose.

I know this is most often a handwaved requirement, but an hour to prepare a new list of incantations? All other classes spend 1 minute per spell level, having only 7 incantations of maximum fifth level would mean 35 minutes if you were to swap them all...

In all honesty I'm not a big fan of the paths, I like them in concept but in application they're rather underwhelming. They're too similar and their features are very minor. The 3rd level feature of converting more Energy is nice (and might be better if you add additional features that interact with Energy), but the 6th level one is very weak. Radiant is one of the best damage types, I don't see many situations why you would change it to necrotic let alone fire. I suggest changing them (preferably for something that interacts with Energy)
Path of Dusk grants Stealth and Darkvision, while Path of Dawn only grants one Proficiency. Also Path of Dusk should probably stipulate what happens if you already have Darkvision (ie. "If you already have Darkvision, its range is extended by 30 feet" or something of the sort)
The Sphere skills are ok, and the level 18 abilities are from other classes at a similar level so they should be fine. I wanna point out you took the Reaction cost off the monk's ability, I don't know if intended or not.

Oh also I'd suggest having the range (and wording of the +1 AC) of Lunar Shield and Binding Fates be the same just for consistency and ease of remembering but it doesn't have to be.

I confess I haven't read through the Incantations in great detail, as at first I was confused as to why some had costs higher than the TW can afford (thought they needed to be updated, I saw now you're using them for your Astromancer too). I'll read them again and provide feedback tomorrow. I admit some of what I have said might change once I have a better picture of the incantations.

Finally I got annoyed at not having the latest version, and since I've been curious about checking out the Homebrewery, I went ahead and transcribed your class there :P (Except all the Incantations)
I'll DM you the edit link. I also made some minor edits while I was at it. Hope you find it useful, but no hard feelings if not.