The Diamond Hook is a grappling hook crafted with 15 Diamonds and is currently the highest tier Gem Hook. Its range is 28 blocks, which is the longest of the Gem Hooks, whereas the regular Grappling Hook only has a range of 18 blocks. It also does not require a Hook from Skeletons, making it a little easier to craft if the player can find the diamonds needed. Gems can be found in the underworld, gained from Slush or Silt when dropped inside an Extractinator, which are rarely found in chests.
The Diamond Grappling Hook has a slightly different icon and graphic from the original Grappling Hook.
Same as the other hooks, when you grappled on the door and opened the door, you will simply launch or get thrown out.