Source: Critical Role

Weapon (greatsword), ??? (requires attunement)

Skingorger is a massive, rust-colored blade once wielded as a symbol of dominance by the ruling overlord in Igrathad. The sword has no hilt, but is one large, solid, rust-colored blade with two handles on the back, so the wielder clutches two open handles on the back of one big, solid glaive. It has the following properties:

• The user gains a +1 to attack and damage rolls made with this weapon.
• While attuned to this greatsword, the user can use their bonus action to take a point of exhaustion to empower the blade for one minute, during which all attacks deal an additional 1d8 acid damage, and it critically hits on a roll of 19 or 20. This feature cannot be used again until the next dawn.