Barbed Split-Cutter

This magical Glaive has an axe-like cutter on its head and a long, barbed spike running through the bottom of the hilt. As a bonus action, you may attempt to spear a target with the barbed spike (Weapon attack roll), forcing the target to make a Strength saving throw upon a hit (DC 10 + Strength modifier + (1/2) Proficiency Bonus). Upon a fail, the barbed spike becomes embedded into the target. Activating the button within the hilt of the glaive triggers the spike to detach from the hilt, connected only by a long steel chain of 5 ft. in length.

Attack rolls made with this weapon gain advantage upon a speared target. While speared, the target is bound within 15 ft. of you and has disadvantage on Dexterity Saving throws. They may only attempt to move over 15 ft. away from you if they succeed in a Strength check against your own and vice versa (you may only attempt to move them if you succeed to overpower their strength). Spells of teleportation may not be cast when this effect is applied. In order to escape the barbed point, the creature must use their action to pull out the barbed spearpoint, making a Constitution Saving throw (DC 15) to withstand the pain. On a failure, the target takes 1d10 piercing damage and must end their turn. Upon a success, the target takes 1d4 piercing damage and is free to continue their turn.

You have a +2 bonus to attack and damage rolls made with this magic weapon. 

Proficiency with a Glaive allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Damage, Combat, Heavy, Reach, Two-Handed, Graze