The Radiant Master

The Radiant Master is a post-Moon Lord mini-boss that spawns during the last 2 minutes of the Radiant Rain event.

Behaviour

 * Flies towards the player, shooting radiant fireballs. These don't damage the player, but spawn a circular stasis field on contact, slowing the player's movement.
 * Consecutively teleports to the left, right, and above the player, immediately charging at them.
 * Flies above the player, occasionally releasing a high-damaging radiant whirlwind.
 * Spawns a ring of stars around itself, shortly shooting them individually.

Once its health drops to 0, it rapidly teleports around the player before dying and dropping its loot.

Trivia

 * The Radiant Master's theme is called "As If The Heavens Cried" and was composed by Ranipla and Universe. The ending of the song plays during the Radiant Master's death animation.
 * Its death animation is a reference to the Soul Master from Hollow Knight, as their death sequences are very similar.

Lore
The Radiant Masters are nothing more than living chronicles, puny and weak-willed magicians who once succumbed to the whispering revelations of the Radiant Rain. It is thanks to their efforts that the Radiant Rain headlong transforms the world, outlining its own beautiful decadence. They're emissaries of Radiant Rain, sent by it's invisible will to earth to collect the souls of those branded with the mark of the light of stars shining in the distance.

They live and exist in order to protect and support the further existence of the Radiant Rain. For them, the meaning of life becomes painstaking and at the same time extremely necessary work on collecting souls in order to amoral their energy into something to satisfy the insatiable hunger of the Radiant Rain, which is always thirsting more and more.

Those whom they have robbed of their souls, as the Radiant Rain once robbed them of themselves, become nothing more than lamenting, hollow shells of their former selves. They become for the Radiant Rain the main weapon of its endless robbery. Unlike mortals, these shells no longer believe in this mirage. They just can't resist it anymore.

Their Radiant Crowns allow them to scatter among the falling heavy stars, becoming one with them. Each curl of the fog of the Radiant Rain is a wriggling tendril of some living, seeking creature along which the Radiant Masters move between the gaping stars.