Response: To find all 13 Emerald Gems in the Haunted Towers of Luigi’s Mansion 2 HD, follow these detailed steps:

1. Emerald Gem 1 – Tower Lobby
– Location: Tower Lobby (F1)
– Mission: B-1 A Job for a Plumber
– How to Find:
– Run behind the stairs in the Tower Lobby to find a hidden entrance.
– Move along the path to get the Circle Emerald.

2. Emerald Gem 2 – Laboratory
– Location: Laboratory (F2-3)
– Mission: B-1 A Job for a Plumber
– How to Find:
– Use the balloon bulb to float your way to the left-hand side of the room.
– Descend to the opening at the top of the broken tank and vacuum the webs to retrieve the Triangle Emerald.

3. Emerald Gem 3 – Garden
– Location: Garden (F1)
– Mission: B-2 The Pinwheel Gate
– How to Find:
– Water the plant on the southeastern corner of the Garden after defeating the Greenies.
– Flash the plant with the Strobulb to get the gem.

4. Emerald Gem 4 – Botany Lab
– Location: Botany Lab (F2)
– Mission: B-2 The Pinwheel Gate
– How to Find:
– Place a bucket under the pipe in the southwestern corner of the room.
– Activate the water pump with a strong Strobulb blast to water the plants near the steps.
– Flash the plants with your Poltergust to reveal the gem.

5. Emerald Gem 5 – Seedling Laboratory
– Location: Seedling Laboratory (F3)
– Mission: B-2 The Pinwheel Gate
– How to Find:
– Shoot the mouse using the walnut launcher in the center of the Seedling Laboratory to get the gem.

6. Emerald Gem 6 – West Garden
– Location: West Garden (F1)
– Mission: B-3 Graveyard Shift
– How to Find:
– There is a chest behind the carnivore plant in West Garden. Remove the plant to access the chest and get the gem.

7. Emerald Gem 7 – Hollow Tree
– Location: Hollow Tree (F1)
– Mission: B-3 Graveyard Shift
– How to Find:
– Burn the webs blocking the path on the left side of the tree to get access to a bucket.
– Fill the bucket with water, then water and flash the plant on the right side of the tree to get the gem.

8. Emerald Gem 8 – Old Graveyard
– Location: Old Graveyard (F1)
– Mission: B-3 Graveyard Shift
– How to Find:
– Look up and use the Poltergust 5000 on the tree behind the first grave to retrieve the gem.

9. Emerald Gem 9 – Skybridge
– Location: Skybridge (F2)
– Mission: B-4 Pool Party
– How to Find:
– Suck up the plant next to the Laboratory’s door on the Skybridge to get the gem.

10. Emerald Gem 10 – Rumpus Room
– Location: Rumpus Room (F3)
– Mission: B-4 Pool Party
– How to Find:
– Walk counterclockwise around the doll in the Rumpus Room. The doll’s head will detach itself, revealing the gem inside.

11. Emerald Gem 11 – Solarium
– Location: Solarium (F3)
– Mission: B-4 Pool Party
– How to Find:
– Use the Dark-Light Device on the coffee table in the Solarium to reveal a chest containing the gem.

12. Emerald Gem 12 – Conservatory
– Location: Conservatory (F5)
– Mission: B-4 Pool Party
– How to Find:
– Use a balloon plant to float up to the balcony on the right side of the Conservatory.
– Reveal the door with the Dark-Light Device and complete the red coin minigame to get the gem.

13. Emerald Gem 13 – West Bathroom
– Location: West Bathroom (F4)
– Mission: B-4 Pool Party
– How to Find:
– Pull on the toilet paper roll in the West Bathroom using the Poltergust 5000 to reveal and claim the last gem.

Collecting all 13 Emerald Gems will unlock a statue of Luigi with the gems on the base, which can be viewed in Professor E. Gadd’s vault.