Suffice to say, you shouldn't kill Wilbur first, and the game even explicitly tells you not to kill Wilbur first. Should Wilbur somehow die before the Swine Prince, the Prince will do Enraged Destruction for the rest of the fight without relenting. Should Wilbur take damage from any means while the Swine Prince is still alive, the Prince will immediately react with Enraged Destruction even despite being stunned or having a DoT proc, causing grievous damage across the entire party along with having a stun proc. Now naturally people's first response when fighting this boss is 'Well I'll just kill the little dude and the Prince won't attack right?' Well, Red Hook is quite aware of this video game trope and has prepared an appropriate countermeasure for this fight. One thing to note as well, should you ever manage to move Wilbur around while Swine King is alive, all of Wilbur's attacks allow him to move 3 spaces back so there's an element of futility to that action. In higher difficulties, Wilbur also gets a free action before his mark to use Bit'o Squeal to try and stun everyone, and he does keep this bonus on Swine Prince's death.

Once you remove the Swine King, Wilbur gains an attack known as Squeal which hits everyone for 1 damage and has a small chance to stun. Should the marks be removed from a target, Swine Prince will instead do Wild Flailing with both reduced accuracy and damage. Once the mark is set, Swine Prince will follow afterward with either Obliterate Body on the single mark, or Obliterate Masses on the pair, dealing a heavy amount of damage on anyone unfortunate enough to be targeted. At the beginning of each round, Wilbur will more than often get the first turn with his insane speed modifier, which he will commit to using either End This One! on a single target, or End These Two on two targets, to mark them and deal 1 point of damage.

The Swine Prince is a boss fight that operates on the Marked mechanic, and will make that quite known with his attacks. Being one of the few prestigious enemies with the 'Gigantic' size classification along with holding the heavyweight title of biggest newbie trap, this boss is very intimidating but can be easily manipulated once you know his mechanics.

The Swine Prince and his buddy Wilbur are part of the OG boss crew, taking up the first boss fight of the Warrens. Part 12: Boss Guide: Swine King & Wilbur Swine Prince & Wilbur

Darkest dungeon warrens trap