The Castle Guard are four minor characters who guard Greenhorne Castle inside and out.
|"If it's a royal palace or a hill of beans, he'll defend it with his life."|
The Serious Soldier stands at the gate of the castle, preventing the player from entering before they obtain the Mayor's Introduction. He also prevents the player from approaching Neksdor before finishing every Greenhorne quest. He stands at the right side next to the door going to The Throne Room.
- When you first approach: "You are approaching Greenhorne Castle. I'm sorry, but I can't let..."
- With Mayor's Introduction: "Oh! You have a letter of introduction from the mayor!"
- In the Demo: "Unfortunately, this is as far as you can go in this demo. However, if I may say so... a grand adventure awaits in the full version of the game!"
- "This is King [King's Name]'s castle. Mind your manners."
- "Ugh, we just let the enemy walk in... A huge monster you've never seen the likes of."
- "The next kingdom is beyond the mountains to the east. That's where the prince is headed."
|"Doesn't mind slacking off. It's Greenhorne, for crying out loud."|
The Lax Soldier stands at the left side next to the door going to The Throne Room.
- "The king has a lot of time to sit around and eat. Goes to show what a peaceful country we are."
- "Oh, please no! Forgive me!"
- "The Dark Lord was even bigger than the king!"
Royal Support (Left)
|"He looks like he's trying hard, but he tends to daydream...a lot."|
His role is to support the King's throne at the left side.
- "It's a lot of work supporting the king... You've got to be really committed. You've got to take it super seriously."
- "I'm rippled with muscles under this armor. But I'm not much good in a fight."
Royal Support (Right)
|"Eternally loyal to the king, but a bit too set in his ways."|
His role is to support the King's throne at the right side.
- "I have but one job. I support the king. It's a... heavy task."
- "I have but one job. I support the king. Except for when that entails fighting monsters."
- In Oceania and European regions, Royal Support (Left) is known as "Left Royal Support" and Royal Support (Right) as "Right Royal Support".
- Despite appearing in the same segment as the King in the credits, their names and roles aren't mentioned when the curtains close.
- This is most likely due to them having a minor role, with the Miis chosen being randomly generated before the player can select which Mii plays which respective role.