Insane Mode

Insane Mode is a post Moon Lord version of Hardmode entered by killing the Moon Lord for the fifteenth time.

World Evils
The old World Evils, Corruption/Crimson and Hallow, will begin to "organize," spreading quickly and creating houses similar to the underworld's Obsidian and Hellstone towers. They will now build blocks across gaps, making quarantine impossible, and removing all of the surface Evils is an integral part in the beginning of Insane Mode. Along with the original two (three if Crimson/Corruption have been introduced into a world originally containing the other), either The Chaos, a hellish combination of Corruption, Crimson, and Hallow, or The Winch, a monstrously mechanical place slowly devouring the world, will spawn into existence, taking over either the left or right ocean.

Ores
After killing the fifteenth Moon Lord, the world will enter Hardmode, spawning in two of six new ores. The world will pick randomly between Pianite or Glassite, Oblonite or Thonorum, and Vannelite or Ganadium. However, the last pair will spawn in rare but huge chunks only after the Chaotic Bosses (Psychosis/Brothers Jaw, Cranius/Master Ludd, Wall of Pain) have been defeated. The more times each of these bosses is killed, the more Vannelite/Ganadium will spawn. The other two pairs will spawn in large quantities at the beginning of Insane Mode. Armor and weapons made from the first two pairs are almost required to battle the first Insane Mode bosses, as all pre-Insane Mode weapons do 1/6 of their original damage to Insane Mode enemies and bosses.

Objectives
The planned extent of Insane Mode is far larger in terms of content than all Hardmode and Pre-Hardmode content put together. Here is a list of all Insane Mode objectives (as of now, more content will be added soon).
 * Obtain Pianite/Glassite armor and preferred Pianite/Glassite weapon.
 * Venture deeper into the cavers and obtain Oblonite/Thonorum armor and weapons.
 * Kill Psychosis (corruption) or Brothers Jaw (crimson). Summon them by removing all of that world evil's surface biome.
 * Obtain Vannelite/Ganadium armor and preferred weapon.
 * Kill Hallord (optional, to get Souls of Bright).
 * Kill Cranius/Master Ludd.
 * Kill the Laboratory defender.
 * Enter the Lab and obtain Megametal/Uranium armor.
 * Kill War Machine I and II (II is optional, and the only useful materials gained from II are Souls of Fight)
 * Kill the Cyborg.
 * Head to Atlantis.
 * Kill the Atlantian King miniboss.
 * Obtain the cursed tentacle.
 * Go mining in the Unerground Tundra for Frost Granite.
 * Kill Ibala by summoning him with the Golden Fishing Pole using the Cursed Tentacle as bait.
 * Obtain the Chain of Demons.
 * Kill the Son of Cthulu.
 * Complete the Nature Events and create you preferred set of Elemental Armor using the fragments from the Nature Events and Frost Granite.
 * Head to the left Ocean to battle the Cthulu Idol.
 * Kill the Cthulu Idol. (End of Current Insane Mode, much more content planned)