Silk

Silk is Hornet's source of energy in Hollow Knight: Silksong. It is similar to SOUL which the Knight uses in Hollow Knight.

In-game, Silk is represented on the HUD by a bar with several strands. Hornet starts with 9 strands of Silk and can acquire more throughout her journey, up to a maximum of 15.

Usage/Abilities
Silk can be used to Bind, quickly healing three masks.

Grapple: Hornet charges up for one moment, before using 2 strands of Silk to throw her Needle  forward. A thread of Silk connected the Needle to Hornet and if the Needle hits a a piece of the environment, or an enemy, Travelling to them, damaging them as well. Hitting an enemy with this ability restores Silk. The ability can be used indefinitely, without landing on the ground, and so long as there is Silk available.

Gossamer Storm: While airborne, Hornet uses 5 strands of Silk to cause threads of Silk to lash out around her in an area of effect. This is similar to the effect of the Thorns of Agony Charm in Hollow Knight. This attack does not restore Silk.

Silk Spear: Hornet uses 4 strands of Silk to attach a thread to her Needle, throwing it out and pulling it back in quick succession. This attack can hit multiple enemies and does not restore Silk.

Battle Stance: Hornet can also perform a taunt, similar to the start of her boss battles in Hollow Knight. She bends down, with her head forward, and a Silk thread comes out the start of the needle, and twirls around her. Though this visually uses Silk, it does not deplete her Silk meter.

Parry: Hornet uses 4 strands of Silk to block incoming damage, followed by a dash attack. Though this visually does not use Silk, it depletes her Silk meter.

Silk Dash: Hornet uses 3 strands of Silk to dash forward, becoming impervious to enemies and dealing damage to anything in her path. Hitting enemies with this ability does not restore Silk.

Attacking Enemies
Enemies struck with the Needle cause Hornet to gain Silk at a rate of 1 strand per hit.

Silk Spindles
Silk Spindles are found across all of Pharloom. When hit with the Needle, they release Strands of Silk that are absorbed, granting 3 Strand of Silk each time they are struck. After a certain number of hits, the Silk Spindle runs out and no longer gives Silk. They are similar to Hollow Knight's Soul Totems.

Webs
Webs are found in Moss Grotto, in an unknown area. There are webs on sets of vines, potentially left by Weavers. Each web gives 3 silk strands.