Jetshift/Possessor, Purgatory Incarnate

Possessor, Purgatory Incarnate is a pre-Hardmode boss that is fought anywhere in the world at night. It is one of the two optional bosses in the mod, the other one being The Annihilation. It is recommended to be fought, as it drops loot that is incredibly useful.

Spawn
Possessor does not spawn on its own and requires a to be summoned. This can only be done at night, as attempting to summon it during the day will have no effect.

Behaviour
Possessor chases down the player(s) throughout the fight while shooting Spirit Flames and Demon Scythes. It occasionally stops to fire a ring of ghastly projectiles, which linger for a short period of time. When it's health drops to or below 25%, it will double it's max health and regenerate to full while transitioning into its second phase. All players are unable to deal damage to it while this is happening.

Possessor, during it's second phase, will attempt to dash into the player(s). It has a faster attack rate, so it will attempt to overwhelm the player with Demon Scythes and Spirit Flames. Occasionally, it will summon a mirror which will circle around Possessor in an attempt to hit the player(s). If Possessor is under 25% health, it will summon Anti-Light Swords which will attempt to dash into the player at a rapid pace. All of this continues until either the player(s) or The Possessor dies.

If Possessor is not beaten by dawn, it will speed up to an extreme speed and instantly kill all players in the vicinity on contact. It is still possible to kill Possessor in this phase, but players are put at an extreme disadvantage. Possessor will never return to it's original form, even if it is still alive until the next night.

Notes and Tips

 * Circling around Possessor is a good way to dodge all incoming projectiles. However, agility is required to do this, as movement in pre-Hardmode is severely limited.
 * While killing Possessor during the day is possible, it takes forever and isn't recommended. Despite this, Possessor will still drop loot when killed.
 * Attempting to run away from Possessor during Phase 1 will allow it's Demon Scythes to easily hit the player, especially at great distances.

Trivia

 * Possessor's theme is Haunted Depths, which is composed by the artist Shadow Figure.