Groundlings (5e PC Race)

"Badger Knight", by Tyler Blake

@POCGamer has been documenting the various demihuman/humanoid creatures that D&D (particularly AD&D) has made up, in an effort to shake up the standard Forgotten Realms/Greyhawk "humanity ascendant" worldbuilding so prevalent in the game. In one twitter thread he discusses the groundlings, who are dwarf/badger hybrids (!?) created by the Zhentarim to be assassins (???)

Specifically, what have they been doing in the 100+ years following the destruction of Zhentil Keep?
As a side note, they appear in the following:

• "The Family Business", Realms of Valor (1993), an anthology of short stories
• Polyhedron #93 (1993), where they and other monsters from the above book receive stats
• Monstrous Compendium Annual Vol IV (1998), reprints their stats
• Monsters of Faerûn (2001), prints their 3.0 stats

And the only relevant in-universe dates that I can find are:
1261 DR, Manshoon founds the Zhentarim
1355 DR, Events of  "The Family Business"
1383 DR, Shadovar raze Zhentil Keep
1490+ DR, Present day

Why Is This Interesting?

Assuming their creation doesn't predate the Zhentarim, the oldest groundlings are still well within the dwarven lifespan of ~350 years. That's like if human/animal hybrids escaped Doctor Moreau's island in the 1950s. Or consider: here are Black Americans alive today whose grandparents were slaves in the South. Imagine what their society would be like if those grandparents were themselves still alive? Even if they reach physical maturity faster than humans (if they don't, it really begs the question of why the Zhentarim used dwarves as slave stock), that memory of recent enslavement is still extremely fresh.

The very existence of groundlings would probably be anathema to other dwarves. Oh, the LG and NG-aligned ones would take pity on them, but the discomfort and loss for words would be plain to see. As half-badgers, the groundlings can probably smell the disgust on anyone who understands what they are. I have a soft spot for Eberron's warforged, who must negotiate a world where they're technically free and equal, but who are very much an inconvenience for the society that created them, and a constant physical reminder of the atrocities of the Last War.

Being loosely connected to dwarves allows a groundling player to define their own relationship to culture. Are they desperate to reclaim the heritage that was suppressed by their (or their parents') Zhentarim masters? Or are they eager to forge an identity for themselves as far as possible from their dwarven ancestors?

I totally believe there was an underground railroad before the fall of Zhentil Keep, with groundling assassins faking their own deaths, undermining the Zhentarim throughout the region, sabotaging their defenses against the shadovar. In any case, as escapees from a wizard fortress, they would have a bunch of sweet looted arcane knowledge, probably piecemeal but which they have been refining and innovating upon to create their own unique wizarding tradition.
Obviously, since they're a player faction in DDAL, all the official hardcovers have plot hooks related to Zhentarim PCs and NPCs. What do groundling PCs do when the shady contact they meet is Zhentarim? Conversely, what do the PCs do when their lead is abducted or killed by groundling NPCs?

Groundling Traits

artist: Tony DiTerlizzi

Note that while groundlings are of dwarven origin, they do not have all the standard dwarven traits. For readability, instead of defining them as a subrace and listing what they don't inherit, the following lists all their traits, including all the broader dwarf traits they do inherit.

Ability Score Increase. Your Constitution score increases by 2, and your Intelligence score increases by 1.

Age. Groundlings mature faster than humans, reaching physical adulthood after 10 years. Surviving members of the first generation are no older than 230, and their maximum lifespan is unknown.

Alignment. The Zhentarim suppressed the dwarven heritage of their creations as best they could, even their language. After a century of freedom, the groundlings still keep to themselves and have no ties to other dwarves. Groundlings tend toward no particular alignment, lawful or otherwise.

Size. Groundlings have the same height and weight as dwarves: between 4 and 5 feet tall and an average of 150 pounds. Your size is Medium.

Speed. Your base walking speed is 25 feet. Your speed is not reduced by wearing heavy armor.

Burrower. You can dig 5-foot-wide tunnels in loose or packed earth, but not through stone, at a rate equal to 25 feet every 10 minutes. The Zhentarim used to magically enhance their slaves' burrowing skills, and this magic lies dormant within you. As a bonus action, you, or a spellcaster able to touch you, can sacrifice a spell slot to give you a burrow speed of 10 feet × the spell slot's level, for 1 minute. This magical effect can be dispelled but does not require concentration to maintain.

Dwarven Resilience. You have advantage on saving throws against poison, and you have resistance against poison damage.

Natural Attacks. Your bite and claws are natural melee weapons with which you are proficient. Your bite deals 1d8 piercing damage, and your claws deal 1d6 slashing damage. Your claws have the light and finesse properties.

Nosewise. You have advantage on Wisdom (Perception) checks that rely on smell. If you find an object recently worn or handled by a creature and which has been minimally handled by other creatures since then, you can pick up its scent as an action. For as long as you have that creature's scent, you have advantage on Wisdom (Survival) checks to track it. You can hold a number of scents in your mind equal to your Wisdom modifier (minimum 1); picking up additional scents requires you to forget a previous one.

Sunlight Sensitivity. You have disadvantage on attack rolls and on Wisdom (Perception) checks that rely on sight when you, the target of your attack, or whatever you are trying to perceive is in direct sunlight

Tracking Skills. Choose one of the following: Athletics, Investigation, Perception, Stealth, Survival. You gain proficiency in the chosen skill.

Languages. You can speak, read, and write Common, and comprehend spoken Dwarvish. Your speech is likely physically impeded by your badger-like jaw.