Collector

The Collector is a strange being who collects bugs.

Location
The Collector is locked in the Tower of Love, which can only be accessed if you found the Love Key in the Queen's Gardens. The Tower can only be entered from the deep shaft with an elevator between Kingdom's Edge and the City of Tears. It can be exited into King's Station, however, after flipping a switch.

Physical Description
The Collector is a tall shadow-like being with four arms and white glowing eyes.

Attacks
The Collector erratically jumps around the room, avoiding attacks and occasionally trying to grab the Knight. The main threat in the battle comes from the glass jars it will rain down from the ceiling. They deal contact damage if they fall on the Hollow Knight, and release enemies when they shatter against the floor. Those enemies are typically not very challenging ones, including vengeflies, baldurs and aspids.

Tactics
As the fight progresses, the Collector will get faster and more aggressive. Keep on your guard and destroy all the basic enemies it creates, as to prevent them from overwhelming you. Additionally, the spawned enemies act as free soul charge, giving you more opportunities to attack with spells or heal. Be careful with when you heal, as the Collector is fast, and its movement pattern can be difficult to telegraph. As always, Quick Focus can be quite helpful. Be wary of its grab attack, although it doesn't seem to use it too often. To summarize, get in as many hits as you can while remaining on your guard.

Upon defeat, the Collector will remain motionless for a moment, giving you the opportunity to hit it with the Dream Nail if you have it. You can then hit it repeatedly with your Nail to finish it off.

Trivia

 * The Collector is the reason the Grubs are in glass bottles spread all over Hallownest. After it is killed, you can get the Collector's Map, which will show the locations of Grubs you have not yet rescued on the map.
 * The Collector seems to be made from shadow, similarly to the Hollow Knight. Because of this, it can be surmised it is a creature of the Abyss.
 * The battle theme of The Collector is Decisive Battle, but it is slightly distorted.
 * The Collector constantly laughs and giggles, even in battle. You can also hear its disturbing laughter as you approach the locked door that leads to its Tower.
 * If you die to the Collector, upon your return, you will find your Shade trapped in a glass jar.
 * Striking the Collector with the Dream Nail will reveal that it has an obsession with preserving natural beauty.
 * Once you free all the grubs, they will be eaten by their own father, which could be what the Collector was trying to prevent all along. This makes it debatable whether the Collector is truly a villain.
 * However, the grubs can still be heard inside the father, which could mean that the grubs are undergoing the next stage of their lives and the father is meant to 'eat' them. This is supported by the description of the charm Grubberfly's Elegy, along with the name of the achievement 'Metamorphosis'.