Goo Lasso

The Goo Lasso is a Hardmode weapon that can have a 12.50% chance to drop from the King Slime if the boss was killed with a sword bound with a Spirit-Studded Tome.

It is different from a grappling hook. It can be thrown like a fishing rod, and if it makes contact with any monster, it wraps around the monster and can be thrown when the player "throws" the lasso like a fishing rod.