Boneslinger

You see bone as more than a warning that a creature has died.  Bone contains information, contains beauty, yet most choose to pass it by.  You, on the other hand, have learned how to decorate bone.  You have learned how to fight with bone.  You can even detect subtle contours on the bones of other creatures which grant insight to their previous life.

Scrimshaw

Starting when you select this subclass at 3rd level, you gain proficiency in the use of woodcarver's tools. Additionally, you may use bone as a material while using woodcarver's tools.

When working with bone, you may create a bone shiv. A bone shiv is an improvised weapon which a Boneslinger may wield as though it were a dagger, with all associated traits and bonuses.

At 13th level, your crafting ability improves.  When working with bone from highly magical creatures, any bone shivs you craft may be considered magical for the purposes of overcoming resistances.  At your DM's discretion, they may also be forged with special abilities which reflect the creature the bone was acquired from.

Dagger Mastery

Beginning at 3rd level, once per turn when you attack with a dagger, you may immediately perform a second attack with a dagger.

Additionally, during your turn, you may freely equip and stow daggers at no action cost.

Bone Fascination

At 9th level, you gain proficiency in the Investigation skill. If you are already proficient in it, you gain proficiency in one of the following skills of your choice: Deception, Insight, Perception, or Stealth. Regardless of proficiency gained, your proficiency bonus is doubled for any ability check you make that uses Investigation.

When performing an Investigation check on a skeleton, you gain advantage. Additionally, you are more prone to decipher subtle traits of the skeleton, including cause of death, dietary habits, subspecies, or causes of decay.

Swift Throw

At 13th level, thrown weapon attacks no longer impose disadvantage at long range.

Bonestorm

 Starting at level 17, you may perform a special thrown weapon attack with a dagger.  This attack negates disadvantage and has a damage die of 4d6.  If the attack would miss, it instead deals half damage and is unable to trigger Sneak Attack.

You may repeat this attack against any number of creatures in range, provided that each attack is against a unique creature.

After using Bonestorm, you can't use it again until you finish a short or long rest.