The Grappling Hook is an item unlocked at String IV. It looks like a non-enchanted Fishing Rod but is not meant for Fishing at all; instead, players can grapple to a block of their choosing within a certain radius. The Grappling Hook has a cooldown of 2 seconds.
The Grappling Hook can be boosted by the set bonus of the Bat Person Armor, removing its cooldown entirely, and increasing its power, and range.
Daysⓘ to acquire 576xString using a Spider Minion (By tier, No fuel, No Minion Upgrades) If the player has multiple minions, divide the number of days by how many minions will be used.
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
0.34
0.34
0.32
0.32
0.29
0.29
0.26
0.26
0.22
0.22
0.17
Daysⓘ to acquire 576xString using a Tarantula Minion (By tier, No fuel, No Minion Upgrades) If the player has multiple minions, divide the number of days by how many minions will be used.
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
0.12
0.12
0.1
0.1
0.09
0.09
0.08
0.08
0.06
0.06
0.04
Trivia
Combining this with the double-jump bonus of the Spider's Boots, players can fly as Technoblade demonstrated in his video "Flying In Skyblock".
Due to the Grappling Hook's cheap, early game cost, some aspects of the game are built knowing the player has access to the Grappling Hook.
The Grappling Hook makes it far easier to collect Fairy Souls.
Finding Dungeon Secrets is much easier with the Grappling Hook.
The Grappling Hook does not reset a player's downward speed, and as such will not prevent fall damage.
Players can use a Grappling Hook while facing down or up to scale walls up to 5 blocks at a time.
Players can scale walls up to 11 blocks with the Bat Person Armor set bonus.
Players can jump right before they grapple in order to increase the distance traveled.
When players use the Grappling Hook before the cooldown is over, the text in chat will display "Whoa! Slow down there!".
Players can still use it as a fishing rod; however, players will not receive anything if they reel something in, and instead will get flung forward. It cannot have any Fishing RodEnchantments applied to it.
The Grappling Hook also appears as a gadget for Hypixel lobbies.
As counter-intuitive as it sounds, players wishing to use the Grappling Hook and Bat Person Armor who wish to cross long distances in the air should consider moving backwards while in the air before reeling their rod in, as the further the distance between the player and the "hook" (Fishing Bobber), the faster the player will move when they reel in the cast.
3x Enchanted String and 
2x Sticks. (576 String)
Spider's Boots, players can fly as Technoblade demonstrated in his video "Flying In Skyblock".
Added Grappling Hook.