Skeletron Prime

. "You feel the air getting colder around you..."

Skeletron Prime is a Hardmode Mechanical Boss which is a much harder version of Skeletron. He is summoned with the Mechanical Skull at night. Players have until dawn to kill him. He can also randomly spawn at dusk in Hardmode if he has not yet been defeated, in this case signaling his approach via the chat message, "You feel the air getting colder around you" or "The air is getting colder around you".

Attacks
Skeletron Prime has four limbs which are all immune to the Poisoned and On Fire! debuffs:


 * Prime Cannon fires flashing bombs that do not destroy blocks and isn't always pointed at a player.
 * Prime Laser shoots Death Lasers similar to those of Retinazer and The Destroyer, and is always pointed at a player.
 * Prime Saw and the Prime Vice swipe around, dealing large amounts of melee damage.

Skeletron Prime's head is immune to the Cursed Inferno debuff, and performs a headspin attack similar to the pre-hardmode Skeletron's headspin attack. During this, his damage and defense double (unlike Skeletron, whose defense reduces to 0). The Prime Saw homes in at players during this phase, even going hundreds of feet away in some cases.

Prime himself is much more mobile than his predecessor, and will regularly move off-screen, which can make him difficult to hit reliably with ranged weapons.

Like Skeletron, if he is not dead by dawn he will begin to dish out instant kills and will take only 1 damage from attacks (2 for critical hits).

Tips

 * Standing on platforms far from blocks can mostly nullify the effects of the Prime Cannon, as its projectiles only detonate on blocks, while passing through platforms harmlessly.
 * Skeletron Prime can be the most profitable boss in the game, as the Souls of Fright can be crafted into Naughty Present to summon the Frost Moon, netting large amounts of money per 5 souls.
 * In multiplayer, the Prime Cannon and the Prime Laser will point at the player Skeletron Prime is attacking.
 * Skeletron Prime can be debuffed by the Golden Shower which can make destroying the limbs easier

Trivia

 * The boss Cortez, from "Paper Mario: The Thousand Year Door" may have influenced Skeletron Prime, as Cortez's final form is a floating skull surrounded by four different levitating weapons, all of different attack powers and methods.
 * His name may have been inspired by Optimus Prime, a robotic character from the Transformers franchise.