Lost Kin

After acquiring the Dream Nail, the player can re-enter the arena and strike the Broken Vessel's corpse with the Dream Nail to be taken to an arena to fight the Lost Kin.

Attacks
Like the Failed Champion and Soul Tyrant, the Lost Kin has the same moveset as the Broken Vessel, but will spam their attacks near constantly; the Infected Balloons will also spawn more frequently; the Slam spawns six blobs rather than four; and there is no Headbanger attack.

Defeating the Lost Kin grants 400 Essence.

Tactics
Mostly the same as the Broken Vessel.

It's recommended to get rid of the Infected Balloons quickly as they can hit the player when distracted or attempting to Focus. The Balloons are also a good source of SOUL. The Defender's Crest can also be useful since it will kill any approaching balloon instantly. Spore Shroom can achieve a similar effect.

Stay close to them, but never too close. When they perform the Slam attack, jump and move to the left/right slightly just enough to dodge its fall, so the player won't take damage while ending in a convenient position to attack.

The Lost Kin often travels to points in the room by jumping, because of this it is advantageous to mainly remain on the floor and travel under him while the Lost Kin jumps over you, the main reason to jump is to dodge the Slash attack.

As with the other Dream Bosses, Fragile Charms will not break upon death, meaning the player can take advantage of Fragile Heart and Fragile Strength without any risk.