Enma
Forge hundreds of years ago, this blade is known for being named 'The King of Hell'. Only those with strong haki can wield its power if it accepts you
+STR/DEX+Proficiency+4 to hit; 5ft; 3d10+STR/DEX+Proficiency+4 slashing+4d8 necrotic
Special: Doubles the haki dice when doing damage, but the user must succeed a CON save (DC:30) to withstand the drain on the user (4d12 damage). After succeeding 5 rolls in total, you can wield the sword without the haki drain