Implementing Vampiric Bite and Regeneration

I am in the midst of trying to migrate my Curse of Strahd game from Roll20 to Foundry. I am using Midi QOL to automate damage applications so that I don't lose function from what Roll20 did for me. A bunch of things has gone very smoothly, but I am a bit stuck on two of the vampiric abilities:

Vampiric Bite -- On hit: 6 (1d6 + 3) piercing damage plus 7 (2d6) necrotic damage. The target's hit point maximum is reduced by an amount equal to the necrotic damage taken, and the vampire regains hit points equal to that amount. The reduction lasts until the target finishes a long rest -- I'd like to automate the self-heal component and maybe even the mac hit point reduction, though, I'm totally ready to accept just the self-heal portion.  

Regeneration -- The vampire regains 10 hit points at the start of its turn if it has at least 1 hit point and isn't in sunlight or running water. If the vampire takes radiant damage or damage from holy water, this trait doesn't function at the start of the vampire's next turn -- The conditions seem a bit convoluted for automation, so my current goal is just to create a simple action that does self-healing. 

My first step was to search for relevant articles or posts and bounced into a couple of somewhat relevant items which I'll dig through below.  I have posted to Reddit and Discord asking about this, but that will take a while to produce results, if it produces results, so on with my slog. 

YouTube Video

Mr. Weaver's YouTube video titled: Foundry VTT Improving Your Game With Item Macros seems set to get me closer to my goal(s). 

Mr. Weaver includes some useful information in his notes below the video, which I will incorporate here for ease of reference:

Here are some of my personal screenshots for my MIDI-QOl settings: Crymic's Midi Qol Settings

Crymic has gone over some of the more advanced features and setups of macros on his Youtube page. Additionally, his Patreon page includes macros for commonly used spells such as Green-Flame Blade, Viscous Mockery, and more. Many of these macros are free to use but become available to patrons first. Please consider supporting Crymic’s Youtube channel as well as Patreon if you are able. 

Crymic's Foundry VTT Macro Repository

Crymic's YouTube Channel

Crymic's Patreon Postings  

The following modules are assumed by these macros:

1. MIDI-QOL 
2. libwrapper
3. Combat Utility Belt (for some macros) 
4. Item Macro
5. About Time/Times Up (To handle duration) 
6. Dynamic effects using Active Effects 

Vampiric Bite's Healing Effect

The damage portion of Vampiric Bite is simply handled with a basic melee attack.  The challenge is the siphon healing bit.  I found one of Crymic's macros that has a self-healing siphon ability: Nourishing Fire. That seems worth a try. 

Implementing Nourishing Fire

I'll try to follow Crymic's instructions to implement Nourishing Fire (though I'll be giving it to an Actor who has no business having it).  

The first step is to create a Feature and call it Nourishing Fire:

1. Click the Items Directory Icon (suitcase in the top-right menu), 
   
2. Click Create New Item,
3. Enter a name for the feature,
4. Set type drop down to Feature,
5. Click the Create New Item to finish creating the item entry.

It only needs a description and an icon.  Leave everything else as is. 

The only other implementation instruction that Crymic offers are two comments in the macro: 

// Midi-qol on use. 

// Create a feature called Nourishing Fire. This will auto grab the card details and spit them out when done.

I also have the body of the macro, but where to put it and how to hook it to something is less than immediately obvious.  I've signed up as a patron of Crymic and will be tossing him some questions, I'll post my results here.

Apparently, the secret sauce I was missing was:

1. Paste the macro into the Item Macro of the attack (top of the item window),
2. Add ItemMacro to the On Use Macro of the attack's detail page.

That doesn't get me all the way home, but it is encouraging. 

Pre-Existing Solution?

My Reddit post pointed me toward a video by The Stunty DM that appears to address my exact issue, down to choosing the same vampire spawn (Anastraysia) to build it around.  The YouTube video is Foundry VTT - Vampire HP Drain Macro. The Macro Is posted at: https://pastebin.com/AhBjhf1a.

To implement this as part of a Vampire's Bite, I believe the steps are:

1. Remove the secondary (necrotic) damage from the Bite attack (macro will handle this),
2. Create the macro by pasting either into a separate macro or as an Item Macro within the attack,
3. Put the macro to be used in the On Use Macro field (ItemMacro if embedded), 

Done!

That video pointed at the exact solution I needed.  I added some comments and my bite macro was finished.  I then cut it way down and I have a Regen macro as well.  

Three Cheers for Crymic's Macros! ! !