The mod by TorchieLight

When you choose the little knight origin you start with Old Nail sword, And you can upgrade it using a Pale Ore.

The Pale Ore can be crafted with 4 Diamonds and 1 Netherite Ingot in the Crafting Table

To upgrade the Nail put Your Nail and the Pale Ore in the Smithing Table

And There are 4 upgrades for Nails:

1- Old Nail To Sharpened Nail

2- Sharpened Nail To Channelled Nail

3- Channelled Nail To Coiled Nail

4- Coiled Nail To Pure Nail