Ending S - "The god of ultra-violence"

The Outlander's specific ending that is only achieved by him while playing in hardmode. To do so, he must slay a number of monsters and foes and acquire their souls. He can also acquire said souls from using empty scrolls too.

Do note, you still need to visit Le'garde's corpse before you can successfully complete the objectives and get this ending.

The monsters you need to slay (except one) and acquire their souls in order to achieve this ending are these: In order to acquire their souls, you need a soulstone (except the Black Witch. Simply defeat it and you will acquire their soul from their defeat, though it is still somewhat buggy, so use an Empty Scroll instead and ask for her soul).
 * Black Witch
 * Iron Shakespeare
 * Butterfly
 * Crow Mauler
 * Cavemother
 * Salmonsnake
 * White Angel
 * Old Guardian
 * Tormented One
 * Valteil
 * François

Note that slaying the Butterfly won't get you their soul. You need to destroy the purple organ of the God of the Depths within the Temple of the True King in the past to acquire their soul (to get to this place, you need to deliver to the Nameless statue the Souls of Endless, Enlightenment, and Torment, which are respectively acquired from Nilvan, Valteil, and Chambara).

This can all be bypassed via the exploit of using the Empty Scrolls you can get from searching bookshelves. If you get lucky that is with the RNG.

After achieving these unique souls, a message will pop up, saying about sensing that all of the evil in the dungeons have been cleansed. After receiving this message, simply leave the dungeons via the way you came.

That's it. Enjoy Ending S - "The god of ultra-violence".

Tips

 * Try to get Isayah's Iron Mask via killing him, since it will help against Crow Mauler's Flock of Crows ability.
 * Not recommended to do this alone. You can get help via Necromancy, Blood Magic, and the Demon Seed, as getting and recruiting the normal companions is disabled in Hardmode.
 * Try to get Miasma as soon as possible.

Trivia

 * The monster that Ragnvaldr slays in the picture in his Ending S is a creature that looks similar to the NPC, Iki Turso.