Demons are a huge part of the Dark Souls world. Long ago, the Witch of Izalith created the Chaos Flame and spawned all true demons from the Bed of Chaos. Since then, the flames spread outward, influencing many different lands and peoples. All those of demonic origin are mighty in one regard or another, but some are absolutely monstrous to behold.
These fiends are not only intimidating but dangerous as well. Some belch lava while others crush their foes with Hellish strength. Regardless of their methods, there are a few that stand out as particularly deadly.
10 Bounding Demon
These brutes were not technically birthed from the Bed of Chaos, though due to their sinister being and residing in Izalith, they fit the name well enough. They are actually the lower halves of dragons; the legs and tail portions. Separated from the rest of their bodies by either rot or other means, they now prowl about the lava lakes blindly. Though, if one is foolish enough to engage them while unprepared, these Bounding Demons could very well stomp them into the singed soil with a flurry of devastating attacks.
9 Titanite Demon
These faceless stone foes can be found all over Lordran, and their connection to the Witch of Izalith is hazy at best. From the description on the upgrade material Demon Titanite that they drop when defeated, it can be learned that these brawny adversaries arose from Titanite Slabs after the nameless blacksmith deity died. It is possible that this god died during the war with the dragons long ago and found some way to pass on his might. Or maybe he did not die at all but became all of the Titanite Demons throughout Lordran; possibly even with the help of those gods who possess the Lord Souls.
8 Stray Demon (Dark Souls 3)
This behemoth can be found far from the flames of their homeland. And far from flame, in general, for the only pyromancy that they use is Boulder Smash, a spell that can be transposed from this demon's soul. Preferring to clobber their enemies with stones or their massive mace, this ashen monster can potentially stagger most players into compromising situations.
7 Demon (Dark Souls 3)
Their name may be simple, but these fiends are some of the most dangerous minibosses in Dark Souls 3. With explosive power and high aggression, they will relentlessly assault the Ashen One and any nearby.
These are among the last few remaining demons though, as certain item descriptions say they are going extinct. This can further be proven when one travels to the Smouldering Lake, which is littered with the corpses of demons.
6 Demon Firesage
An optional boss in the Demon Ruins, this flaming foe is one of the few intelligent enough to use spells. This, in addition to their brute strength, makes them dangerous at any range. This master of the original fire arts, which existed even before the Witch of Izalith created the Bed of Chaos and modern pyromanices, is one with fire. Wreathed in a cloak of orange flames, this demon uses a massive catalyst to send out super-heated shockwaves that can be difficult to avoid and knocks the player down, opening them up to further attacks.
5 Ceaseless Discharge
A molten giant that is not initially hostile, they can be found staring at the remains of a deceased sister. Long ago, lore on the Orange Charred Ring states that they were the youngest child, and only son, of the Witch of Izalith. When his mother created the Chaos Flame, it sent out a force of twisting energy that warped all it touched into demons. The first to be affected were the Witch and her children. Long after changing into this colossus, the Ceaseless Discharge remains in Izalith and only fights the player if they desecrate the body of his sister by taking the items there. If one dares to tangle with this beast's orange tendrils, be prepared for a fight upon a ledge with an enraged titan wielding devastating slams and unblockable fire attacks.
4 Centipede Demon
Before the Ceaseless Discharge was a demon it was a boy. One born with an illness that covered his body in sores inflamed with lava. To ease his pain, his sisters gave him the Orange Charred Ring, which reduces damage taken by lava.
Sadly, the boy accidentally dropped it into a molten lake and from that spot eventually spawned the Centipede Demon when the Bed of Chaos was created. This hideous adversary is the epitome of chaos and is pure destruction. With tremendous reach and immensely powerful strikes, it is one of the hardest-hitting bosses in the game.
3 Old Demon King
An ancient demonic monarch that has existed since before the Chaos Flame was extinguished long ago. Having outlived most other demons, the king now resides in the Smouldering Lake, surrounded by the corpses of his kin. Tired, but not dead, the Ashen One can give this fiery elder one last great battle before their end. And what a battle it can be with fire being expelled from mouth and weapon. Not to mention meteors falling from above at the behest of this master of pyromancy.
2 Demon Prince
At some point the Demon Prince and Prince Lorian did battle. Following this, both suffered greatly; Lorian possibly losing the use of his lower legs and the Demon Prince being slain. Though the prince's soul persisted in the shared memories of the demons, even to the last two: the Demon in Pain and the Demon From Below. If one of these two is felled, it will fulfill some sort of chaotic prophecy and cause the last remaining demon to be reborn as the Demon Prince, the champion of the Old Chaos, and the last scion of demonkind. A being of immense ferocity, capable of destruction few can avoid or withstand.
1 Bed of Chaos
The Bed of Chaos is the Chaos Flame. The Old Chaos is what was created when the Witch of Izalith tried to duplicate the First Flame, but the fires consumed her and melded with her soul. The flame aspect one fights is less of a singular being and more of a force of nature. It is unlike most other bosses in that the Chosen Undead cannot directly hurt it and must instead attack nodes in its roots that will open up access to a Chaos Bug at the center of this burning tree. This Chaos Bug is likely the warped heart of the Witch, so when it is slain the flames will die. And with it, all demons across Lodran will eventually fade, not unlike the First Flame that the Witch of Izalith sought to emulate.