I have a question on the Hypnotic Gaze feature of the Enchanter wizard. If you use HG on, say, a guard outside of a door you are trying to get past can you use this on your action, let the party pass the guard and then use your move to pass through the doorway and lock it behind you even if it is more than 5 feet away? This may be nit picky but the part that says the effect ends if you move more than 5 feet from the target is only mentioned in the paragraph under "on subsequent turns." Does that mean on the initial turn you can move away and the effect not end "until the end of your next turn"

I'm not entirely sure what your question is. When you move 5 feet away, the effect ends, but you can still make it to the door and lock it. Does that answer it?

Yes, I was kind of confused because I wasn't sure if the effect ended on the initial turn of casting, if you moved, since it said it lasts until the end of your next turn. And the 5 feet limit was only under the paragraph of "on subsequent rounds" making it sound like only later rounds that you use your action on would have the 5 foot limit.

I think I just had it messed up in my head, but thanks for the reply

Moved or not, the creature is " charmed by you until the end of your next turn." Every turn, you can re-up the charm if you're still there within 5 feet and use your action again, and at that point it'll break if you at any point move more than 5 away (even mid-turn). But on the initial turn, you are correct, you can Charm-and-dash and the guy won't uncharm until the end of your second turn. The way the effect is worded explicitly makes it work differently the first round of the charm than it does every subsequent round that it is maintained. 

The sentence that says the effect ends when you move does not only apply to subsequent turns, if it did it would be part if the same sentence.

Conversely, the sentence that says that the effect lasts until the end of your next turn does not have an "..., or until you move more than 5 feet away from the creature." Paragraph structure supports the reading that the 5-feet requirement applies to "On subsequent turns...", but I'll concede that it could be read your way as well. Seems a little ambiguous.... Incapacitated is an effect that is meaningful both on-turn and off-turn, so the ability still seems useful either way. 

Hypnotic Gaze

Starting at 2nd level when you choose this school, your soft words and enchanting gaze can magically enthrall another creature. As an action, choose one creature that you can see within 5 feet of you. If the target can see or hear you, it must succeed on a Wisdom saving throw against your wizard spell save DC or be charmed by you until the end of your next turn. The charmed creature’s speed drops to 0, and the creature is incapacitated and visibly dazed.

On subsequent turns, you can use your action to maintain this effect, extending its duration until the end of your next turn. However, the effect ends if you move more than 5 feet away from the creature, if the creature can neither see nor hear you, or if the creature takes damage.

Once the effect ends, or if the creature succeeds on its initial saving throw against this effect, you can’t use this feature on that creature again until you finish a long rest.

The language is pretty clear. If you replace all instances of "the effect" or "this effect" with "hypnotic gaze," (which you can do because that is how pronouns work) you get "Hypnotic gaze ends if you move 5 feet away from the creature."

The first paragraph is what starts the effect and what the effect is and the second paragraph is what ends the effect early or extends its duration. Many spells and effects in 5e use this structure.

If that sentence didn't start with "However,..." I might be inclined to agree with you. But "However,..." links that sentence very very firmly with the sentence preceding it, which starts with "On subsequent turns...". I don't think it's "pretty clear" at all that the "on subsequent turns" rules are intended to limit the initial round. The second paragraph is not what ends it; the first paragraph includes its own ending clause already all on its own ("...until the end of your next turn."). 

I enjoy having steak for dinner. You can eat red meat fully cooked, or eat it nearly raw.

After a steak, sometimes I extend my meal with a nice cookie. However, you have to be sure it's fully cooked, or else you could get food poisoning.

Just a rough quick attempt, but here's an alternative statement with the same general structure as this rule, where "However" makes it clear that the subject of the second sentence of the second paragraph (P2S2) is the first sentence of the second paragraph (P2S1), not the second sentence of the first paragraph (P1S2). Especially since if the subject was P1S2, it would mean that P1S2 was misleading from the get-go, which isn't ideal. I read this rule with section with similar grammar/structure. The first paragraph meant what it said when it laid out that the initial effect lasts until the end of your next turn. And the second paragraph means what it says when you can keep extending that, but only so long as you stay within 5 feet. 

"However" doesn't change the meaning of the sentence. It starts with "however" because it is contrary to the previous sentence which describes extending the effect.

Your example is more confusing than the rule. A better one would be:

You can start a fire with a match that lasts for a few minutes.

You can extend the burn time by adding wood. However, the fire goes out if you pour water on it.

Your argument is that this language implies that the fire can't be put out with water unless you add wood first, but the sentence that the fire goes out is not reliant on how long the fore has burned. (Because of the subject change of this example sounds worse for your position than it is meant to be.)

That’s a good counterpoint. But it leans too much on a logical parallel to make its point when what we’re really trying to pick apart is the grammar involved in paragraph breaks and “howevers,” not the logic of whether the effect should/shouldn’t end. We’re talking about magic, which can work however the sentence describes it as working, not a fire getting a bucket of water dumped on it but ludicrously continuing to burn.

Quote from Chicken_Champ >>

That’s a good counterpoint. But it leans too much on a logical parallel to make its point when what we’re really trying to pick apart is the grammar involved in paragraph breaks and “howevers,” not the logic of whether the effect should/shouldn’t end. We’re talking about magic, which can work however the sentence describes it as working, not a fire getting a bucket of water dumped on it but ludicrously continuing to burn.

 True how about a door with buttons:

You can push a button to open an automatic door which stays open for 10 seconds.

You can push the button again to reset the timer. However the door closes if someone walks through it.

I don't think that language implies the door will stay open for the full 10 seconds if you push the button once and walk through the door.

Let me tweak your sentence slightly to be closer to the original  text though:

You can push a button to open an automatic door which stays open for 10 seconds.

After 10 seconds, you can push the button again to reset the timer for another 10 seconds. However the door closes if someone walks through it.

Your reading essentially skips over the "on subsequent turns" language as so unnecessary, that it didn't even make it into your paraphrase. My reading is that that was very important language calling this out this second section as new rules for new rounds. I think that without that bolded language I would agree with you, but with it, I don't.

I still think the "however" means "regardless of if you extended the time," not "but if you extended the time, then..."

I guess we will just have to chalk this one up to yet another rule written in such a way that it can have more than one interpretation.

I'm not coming down on one side it the other, but if the feature said "regardless" instead of "however" it would be very clear. I couldn't think of a word that could replace however that would make it clear the other way; maybe the designers had the same struggle?

Edit: Maybe I should more thoroughly read the comments. DxJxC said almost the same thing only 1 post above.

Well I'm glad I wasn't the only one reading it as Chicken_Champ. I guess it will be a discussion with the DM when the time comes.

Thanks for all your help.