|Yes, those are Villagers in that cage behind him, just in case you weren't convinced from the costume that he's evil.|
His origins are a mystery, his motivations a riddle, his identity an enigma. The strongest being in the Overworld, the Monarch is believed to wander the Strongholds and castles that dot the world. There are some who say he is the necromancer responsible for the zombies and skeletal archers who plague the world's caverns and nights on the surface. Perhaps it is for this reason that he wields a unique golden sword called the Holy Sword, specifically strong against the undead, to maintain his dominion over his monstrosities.
How such an evil entity came into possession of such a weapon of goodness is a mystery, but the prospect of reclaiming it gives warriors one more reason to face him in battle. It is rumored he is in possession of other mythical artifacts, like the Hammer of Notch, Obsidian Armor, or unique potions and enchantment books.
Unfortunately, a Monarch is rarely without a court, and this one's court consists of a squad of powerful enchantresses. They are certainly skilled with Splash Potions, and rumor has it they are also competent archers with Tipped Arrows, which makes sense as they would have easy access to The End. As if fighting the Monarch wasn't going to be hard enough...
Who knows what lies behind those iron trapdoors that serve as masks? The sinister guards of the Monarch's domains, they can hear instantly when a door, be it wood or iron, has been opened, and they will seek out the intruder with their axes. Destroying doors just makes them angrier. You can try tunneling through the walls, but you never know what stone bricks might be silverfish eggs.
There exists a common misconception that there is only one Doorman, a random killer who stalks humans and Villagers in the dead of night. This is because, despite their loyalty to the Monarch, once in a blue moon a Doorman might wander off into the surface world by accident; they're not very clever. If they come across a survival base or a village...lured by the sound of doors opening and closing...