Senze CR: 4

Medium humanoid (half-elf), neutral

Armor Class: 15 (Studded Leather)

Hit Points: 80

Speed: 30 ft

STR

10 +0

DEX

16 +3

CON

12 +1

INT

14 +2

WIS

16 +3

CHA

10 +0

Saving Throws: Dex +5, Wis +5

Skills: Investigation +4, Perception +5, Stealth +7

Senses: darkvision 120 ft, passive perception 15

Languages: Common, Elven, Thieves’ Cant

Challenge Rating: 4

Proficiency Bonus: +2

Fey Ancestry. Senze has advantage on saving throws against being charmed, and magic can't put her to sleep.
Dead-eye. Attacking at long range doesn't impose disadvantage on Sense's ranged weapon attack rolls and they ignore half and three-quarters cover.
Toxin Cocktails. Jellyfish Sting has a compartment that can hold a toxin ampule prepared by Senze. When she hits with the weapon, she can change the weapons basic toxin to one of her own. Jellyfish neurotoxin (1/long rest). when Sense hits with a ranged weapon attack using Jellyfish Sting, she can force the creature to make a DC 13 Constitution saving throw, becoming Paralyzed for 1 minute on a fail. The creature can make the saving throw again at the end of each of it's turns to end the effect.

Actions

Jellyfish Sting (musket). Ranged Weapon Attack: +5 to hit, reach 480 ft., one target. Hit: 10 1d12+3 piercing damage. Choose one of the Toxin Cocktais to enhance the bullet.
Basic toxin: plus 7 2d6 poison damage on hit.
3/long rest: Snail toxin. Constitution saving throw: DC 13 Failure: speed is reduced by 10ft. untill the end of its next turn.
3/long rest: Shroom toxin. Constitution saving throw: DC 13 Failure: poisoned untill the end of its next turn. Dagger. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 1d4+3 piercing damage.

Bonus Actions

Cunning action. Senze uses the Dash, Disengage, or Hide action.
Precision shot. Senze has Advantage on the next attack roll it makes during the current turn. If that attack hits, the target takes an extra 11 3d6 piercing damage.