Which book has the Duergar in it? This was pretty high on my to do list as my party were deep in the under dark until some wish magic went wrong.

It's in Sword Coast Adventurers Guide (SCAG).

I thought I'd done it for my own use, but had it confused with the Deep Gnome which I have done.

I'll make sure it's done today. Pretty keen to have Scag complete. I just added all the class options in so race options are up next.

Just working on my SCAG stuff atm. Want me to post a Zip of my user file to GIT when I have finished?

Arcane domain, Tiefling variant material.

Warning: Some of the Tiefling traits (Cateyes, 6 fingers, ect. have been house rulled so you may want to make them conform to the SCAG rules).

Send it over and I'll have a look. :)

Like I said, working on it atm. Not sure if I got the bugs out of Arcane Mastery for the Arcane Mastery feature.

I know i was having issues with it and got side tracked by a different issue. Can't remember if I got back to it. :)

Buildign a 17th level character to test it atm.

Thank you so much for making sure the duergar are added as a subrace option. :) Can I ask when it will uploaded for all to use?

I was right, I hadn't finished the Arcane Mastery feature. I'm up to the point where I can select the appropriate spells and they are added to the cleric's spell selection, but when you add them, they are not begin added for free.

Up to now the scripts were working fine, but they were for lower level spells, not 6th, 7th, 8th, and 9th . . .

<Troubleshooting cap time>

Anyone know if the Helper.Free tag can be used on spells over 5th level? The Eval Rules script I'm using works fine up to 5th level spells, then it seems to not work.

Not sure on a public release date however you can always download the files from the link below and copy them into your 5e files.
https://github.com/Sklore/HL_DD_5e_Colab