[5e] Goblin Assassins

Here's some stats for a goblin assassin- mine are acting as spies for  well-organized Hobgoblin mercenary company that is working for the main antagonist in my game, but they could easily be slotted in as Dhakaani goblins for a Eberron campaign.

Goblin Assassin (Rogue 3)
Medium Humanoid, Neutral Evil
Armor Class: 13 (leather)
Hit Points: 15 (3d8)
Speed: 30 ft.

Str 8 (-1) Dex 15 (+2)  Con 10 (0) Int 10 (0) Wis 16 (+3) Cha 7 (-2)
Saving Throws: Dex +4, Int +2

Skills: Stealth +6, Perception +5, Acrobatics +4, Investigation +3, Athletics +3, Sleight of Hand +4
Senses: Darkvision 60 ft., passive Perception 15
Languages: Common, Goblin, Thieves Cant
Challenge: 1

Sneak Attack +2d6 damage 1/round against targets the Goblin has advantage against
Cunning Action: The goblin can take the Hide, Dash, or Disengage action as a bonus action on each of its turns.
Assassinate: The goblin has advantage on any creature that has not yet taken an action in combat. In addition, hits against surprised targets are automatically critical hits.
Poison: Many goblin assassins use poison, particularly on their darts (which are often used to cover an escape). Carrion Crawler Mucus (DMG), Serpent Venom (DMG), and Basic Poison (PHB) are all common.

Actions:
Dagger: Melee or Ranged Weapon Attack, +4 to hit, reach 5 ft., range: 20/60, one target. Hit: 1d4+2 Piercing damage.

Darts (5): Ranged Weapon Attack, +4 to hit, Range 20/60, one target. Hit: 1d4+2 Piercing damage + poison (see below)

Description: While Goblins are not known for being particularly well-focused on any particular task, their natural small size, natural stealth, and basic self-centered ruthlessness can make then useful spies on assassins for a leader who has sufficient strength of will and arms to keep them in line and compel them to stay focused on their mission. Goblin assassins are much more grim and focused than the average Goblin, keen observers who prize their own survival and always have an eye out for potential targets or ambushes. Goblin assassins prefer to strike when their target is totally helpless, infiltrating towns or camps under cover of darkness and having no qualms about killing sleeping victims. Their equipment depends on their mission, but often includes poisons and caltrops that are used to cover their escape in the event that they are discovered or interrupted.

Vows and Codes of Conduct [5e]

Tying game abilities to behavioral restrictions has always been a bumpy road, but I think the new rules provide some interesting options.

Consider a simple code of conduct for a monk or priest:

• No touching money (coins).
• No touching members of the opposite sex out of combat.

If you violate either of these strictures, you lose:

• You proficiency bonus
• Any unspent spell slots

Until your next Long Rest (which you must spend meditating and doing penance, but you can still regain spells as normal- you don't have time to do anything else, however).

Couple of points:

• Keep rules concrete and few in number
• Doesn't have long-term alignment impact- that is a different ball of wax
• Doesn't cripple you by removing all abilities, but is serious enough to not be used willy-nilly
• Restoration is low-impact, but not automatic (because you have to make it until your next safe spot for a long rest)

Likewise, you can take on optional strictures (like "no edged weapons" or "no metal armor"). Doing so gives you Inspiration at the end of the next Long Rest (provided that you didn't break a mandatory vow during the same period).