King Boo Costume
Rule the mansion as the crown-wearing king of the Mario ghosts.
King Boo is the mischievous, crown-wearing leader of the Boos and the main antagonist of the Luigi's Mansion series. Fans of the Mario franchise love this character for his blend of spooky charm and royal flair. The look centers on a ghostly white base topped with his signature oversized, jewel-encrusted gold crown.
- Difficulty
- Easy
- Time
- ~45 min
- Budget
- $20–60
Try it on
See yourself as King Boo
One clear photo of yourself; we render you in this costume — face untouched, full body, about 20 seconds.
One render, $1. No account needed — if it fails you're not charged. Pricing.
Your photo is sent to Google's Gemini API to make the render and isn't used for training. Renders are AI-generated and labelled.
Want a different costume on this photo, or a whole group in costume? Open the Try-On Studio.
What you need for a King Boo costume
Short on time? Buy it ready-made
Spirit Halloween sells the complete King Boo costume — one box instead of 5 pieces.
White poncho, tunic, or oversized t-shirt
A flowy, solid white top or poncho to mimic the rounded, floating shape of a ghost.
DIY: Cut a wavy hemline into a large white bedsheet or oversized white t-shirt.
Gold crown with jewels
A shiny gold crown featuring large red and blue faux gems, matching King Boo's royal accessory.
DIY: Cut a crown shape from gold glitter craft foam and glue on large plastic craft rhinestones.
White pants or leggings
Simple, solid white leggings or slim-fit pants to keep the ghostly monochrome look consistent.
DIY: Use any plain white sweatpants or jeans you already own.
White gloves
Classic white cartoon-style gloves to match his ghostly hands.
Felt face decals
Black, red, and pink felt sheets to cut out King Boo's signature mischievous eyes, open mouth, and tongue.
DIY: Cut the facial features from felt and safety pin or fabric-glue them to the chest of your white top.
Rather not assemble it? See ready-made King Boo costumes at Spirit Halloween ↗
How to put it together
- 1
Put on the white leggings or pants as your base layer.
- 2
Slip on the oversized white t-shirt, tunic, or poncho.
- 3
Cut out two angry eyes from black felt, a wide open mouth from black felt, and a tongue from pink felt.
- 4
Attach the felt facial features to the center chest of your white top using fabric glue or safety pins.
- 5
Put on the white costume gloves.
- 6
Secure the gold jeweled crown on your head, using bobby pins if necessary to keep it upright.
Makeup & hair
Keep your hair hidden under a white wig or slicked back so the focus remains on the crown. If desired, apply white face paint with dark, dramatic eyeshadow around the eyes to enhance the spooky ghost aesthetic.
King Boo for couples, groups, kids & more
- couples
- Pair up with someone dressed as Luigi holding a vacuum cleaner (Poltergust) for a perfect Luigi's Mansion duo.
- group
- Form a Mario villain squad with Bowser, Wario, and Waluigi.
- kids
- Use a white hooded sweatshirt and stick the felt face pieces directly onto the hood, placing a small foam crown on top.
- Plus size
- An oversized white fleece poncho or cape provides a comfortable, flowing, and screen-accurate ghostly drape.
- pet
- A simple white dog cape with a lightweight, elastic-banded gold crown.
Tips
- If trick-or-treating or partying outdoors, wear warm white thermal layers underneath your white top.
- Make sure the crown is lightweight so it stays balanced on your head throughout the night.
- For photos, strike a classic Boo pose by covering your face with your gloved hands as if hiding when someone looks at you.
King Boo costume FAQ
- How do I make a DIY King Boo face?
- Cut two angled, angry eyes and a wide, crescent-shaped open mouth out of black adhesive felt. Cut a rounded tongue out of pink felt and stick it inside the mouth before pressing the pieces onto your white shirt.
- What kind of crown does King Boo wear?
- He wears a classic gold royal crown adorned with large, colorful jewels—traditionally featuring a prominent red ruby or purple gem in the center.
- Is this costume comfortable for walking around?
- Yes, using a white poncho or t-shirt over leggings makes it highly breathable, flexible, and easy to wear all night.
Did you know? King Boo made his very first appearance as the main boss in the 2001 Nintendo GameCube launch title, Luigi's Mansion.