Guide:Empress of Light strategies

The Empress of Light is a Hardmode post-Plantera boss fought in the Hallow.

Spawn Conditions
The Empress of Light can be spawned by killing a Prismatic Lacewing, which is a rare Critter that spawns in the surface Hallow during the night once Plantera has been defeated in the world. As it is a rare creature, it can be detected by the Lifeform Analyzer. The Prismatic Lacewing can only spawn between 7:30PM and 12:00AM, and only one can have spawned in the world at any given time.

Like most critters, the Prismatic Lacewing can be caught with any bug net, which can then be released, and killed, by the player manually. This can be used to spawn the boss at a more desired place and time. However, the critter will almost instantly despawn if released outside of the Hallow, so it must be killed quickly in order to summon the boss.

Time of Day
The Empress of Light, if summoned by a natural spawning Lacewing, will be fought at night. She will enrage if still alive or if summoned during the daytime, causing her attacks to do tens of thousands of damage, instantly killing players who are hit by her attacks. This enraged state is indicated by her attacks turning from rainbow to bright yellow.

She will always drop the Terraprisma if all damage dealt to her was during the day.

Attacks

 * Prismatic Bolts - Summons a cloud of prismatic bolts that home in on the player after a short time. These bolts do not have perfect tracking, and will miss if the player makes a sharp turn as they approach. If enraged, extra bolts are created, and they will spread out more before homing onto the player.
 * Dash Attack - Positions herself to the left or right of the player before charging horizontally in the player’s direction.
 * Sun Dance - Hovers above and slightly to the left of the player and emits 6 rays of light (8 if enraged) that slowly rotate clockwise. 3 sets of rays are created per sun dance, each positioned slightly more clockwise from the last.
 * Everlasting Rainbow - Releases a ring of 13 stars that spiral out clockwise, then spiral back in the same direction. These stars leave behind a trail of light that will damage the player.
 * Ethereal Lance - Summons a swarm of swords that launch in the direction the player was headed when they were summoned, telegraphed by colored beams. These swords are summoned behind where the player was moving, or all around the player if they were stationary. The swords do no damage until launched. If enraged, extra swords are summoned, and they will launch faster.

Attack Pattern
The Empress has set attack patterns for both of her phases.

First Phase
When spawned, the Empress will hover in place for a few seconds before executing the following attacks in order:


 * 1) Prismatic Bolts
 * 2) Dash Attack
 * 3) Sun Dance
 * 4) Dash Attack
 * 5) Everlasting Rainbow
 * 6) Prismatic Bolts
 * 7) Dash Attack
 * 8) Ethereal Lance
 * 9) Dash Attack
 * 10) Everlasting Rainbow

This sequence of attacks will repeat indefinitely until the second phase starts.

Second Phase
When the Empress is below half of her max health, she will disappear for a second, then reappear above the next estimated location of the player before executing a new set of attacks, with slightly shorter attack intervals than before:


 * 1) Ethereal Lance Ver. 2: Summons four evenly spaced waves of swords that travel across the screen, telegraphed by colored beams. The first wave travels from the left side of the screen to the right, the second from right to left, the third wave from top-left to bottom-right, and the fourth wave from top-right to bottom-left.
 * 2) *If enraged, there will instead be six waves of swords that target specific points around the player instead of traveling from one side of the screen to the other. The first wave travels from the left side of the screen to the right of the player, the second wave from the right side to the left of the player, the third wave from top side to the bottom-right of the player, the fourth wave from top side to bottom-left of the player, the fifth wave from the bottom side to top-right of the player, and the sixth wave from the bottom side to top left of the player.
 * 3) Prismatic Bolts
 * 4) Dash Attack
 * 5) *If enraged, she will cast Ethereal Lance after the dash before resuming her normal pattern (targets where the player is rather than where they will be, or do nothing if the player is stationary)
 * 6) Everlasting Rainbow
 * 7) Prismatic Bolts
 * 8) Sun Dance
 * 9) Ethereal Lance
 * 10) Dash Attack
 * 11) Prismatic Bolts (Cast in a circle around the Empress instead of a cloud directly above her)

This sequence of attacks will repeat indefinitely until she is defeated.

Strategies
The Empress of Light is very fast, so a quick mount with infinite flight is useful in combination with a homing weapon.