Hell-bred orcs, a subrace + altered base race

[PhoenixPhyre]

As part of my effort to create "tweaked" variant races/sub-races for all 5e races without sub-races and due to some campaign events, I'm introducing a new subrace for my orcs. Feedback on balance requested. The first part is setting-specific.

Hell-bred
These orcs are the descendants of those orcs that entered Godsfall before the Cataclysm and were altered by abyssal magic during the reign of Kul'Assad. While not demonic themselves, they bear the visible stigma and carry that hellish magic in their blood. Shorter and wider than most orcs, they have reddened skin and more prominent tusks. Unlike Dynastic orcs, they do not consider themselves tribe-bound and live in a society much more similar to a wall-builder. They do not carry the tribal tattoos of other orcs.

Ability Score Increase. Your Charisma score increases by 1.
Fearsome Mien. You gain proficiency in Intimidation.
Abyssal Legacy. You know the resistance cantrip. When you reach 3rd level, you can cast the darkness spell as a 2nd level spell once with this trait and regain the ability to do so once you finish a long rest. When you reach 5th level, you can cast the fear spell as a 3rd-level spell once with this trait and regain the ability to do so when you finish a long rest. Charisma is your spellcasting ability for these spells.

Base Orcish race (note--this replaces the Half-orc and orc races in their entirety. Half-orcs are a sub-race now, not a full race).
Ability Score Increase. Your Strength and Constitution scores each increase by 1.
Age. Orcs mature a little faster than humans, reaching adulthood around age 14. They age slightly faster and rarely live longer than 75 years.
Size. Orcs are somewhat larger and bulkier than humans, and they range from 5’5” to well over 6’. Your size is Medium.
Speed. Your base walking speed is 30 feet.
Darkvision. One of the modifications made by the ancient aelvar was superior vision in dark or dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of grey.
Relentless Endurance. When you are reduced to 0 hit points but not killed outright, you can drop to 1 hit point instead. You can’t use this feature again until you finish a long rest.
Languages. You can speak, read, and write Common and Ard-Teang (Orcish).

[snafuy]

Compared to Half-Orc you're swapping +1 Cha for +1 Str, and 3 spells for Savage Attacks.

On a typical adventuring day, a melee-based character is likely to land 0, 1, or maybe 2 critical hits, giving the Half-Orc 0-2 extra dice of damage per long rest. It's not a very powerful feature.

Resistance, Darkness, and Fear is WAY better.

Volo Orcs don't get Relentless Endurance, so you must be using homebrew for them as well, leaving no basis for comparison.

[PhoenixPhyre]

Compared to Half-Orc you're swapping +1 Cha for +1 Str, and 3 spells for Savage Attacks.

On a typical adventuring day, a melee-based character is likely to land 0, 1, or maybe 2 critical hits, giving the Half-Orc 0-2 extra dice of damage per long rest. It's not a very powerful feature.

Resistance, Darkness, and Fear is WAY better.

Volo Orcs don't get Relentless Endurance, so you must be using homebrew for them as well, leaving no basis for comparison.

Basically, I'm using the base race (essentially splitting the half-orc stat block in half) for orcs and half orcs. The difference for a half-orc vs full orc (of several variety) is just sub-race now.

Do you have suggestions for spells (or similar) replacements? I want something vaguely "fiend warlock"-esque, as these guys are altered in a similar manner.

As a note, I've spoilered the other sub-races for orcs below. I'm more concerned with internal balance.

Spoiler: Other Subraces

Show

Bear Paw
The orcs of tribe Tabar wear the bear paw sigil. The most numerous of the Dynastic orcs, they are the disciplined backbone of the Dynasty’s military.
Ability Score Increase. Your Strength increases by 1 (cumulative with the racial +1).
Disciplined. You have advantage on saving throws against fear effects.
Region of Origin: Choose your region of origin from Baile Duchas, the Kairen Mountains or Safehold.
Savage Attacks. When you score a critical hit with a melee weapon attack, you can roll one of the weapon’s damage dice one additional time and add it to the extra damage of the critical hit.

Half-blood
Half-orcs inherit some of the flexibility of their human ancestors.
Half-feat. You gain a feat of your choice from the following list: Actor, Athlete, Durable, Keen Mind, Lightly Armored, Linguist, Observant, Orcish Fury (XGtE), Resilient, Tavern-Brawler, or Weapon-master

Hammer Stroke
The orcs of tribe Kard bear the sigil of a hammer. They are the crafters and miners of the orcish forces, as well as the most cosmopolitan of the orcs.
Ability Score Increase. Your Charisma increases by 1.
Craftsmen. You gain proficiency in two artisan’s tools of your choice.
Hammer Blow. When you score a critical hit with a melee weapon attack, the target must make a Strength saving throw against a DC of 8 + your Strength modifier + your proficiency bonus or be knocked prone.
Region of Origin: Choose your region of origin from Baile Duchas, Byarmarsh, or Safehold.

Triquetra
The orcs of clan Skem bear the sigil of the three-pointed leaf. The core of the spiritual life of the Dynastic tribes, they are famous for training shamans and spell-casters.
Ability Score Increase. Your Wisdom score increases by 1.
Naturally Attuned. You gain proficiency in Nature and Insight.
Decisive Spell. When you score a critical hit with a spell attack or an opponent rolls a 1 on a saving throw against a spell you cast that deals damage, you can roll one of the spells’ damage dice and add it to the damage total.

Wilder
The wildest of the Dynastic tribes, clan Ko’s sigil is a stylized sunburst. They range the northern boundary of the Dynasty, protecting the nation from hostile orcs as well as exploring the pre-Cataclysm ruins for useful artifacts.
Ability Score Increase. Your Dexterity score increases by 1.
Ruin Hunter. You gain proficiency in Survival and Investigation.
Point-blank Shot. You do not suffer disadvantage for making a ranged weapon attack when an opponent is within 5 feet of you.