Rooftop (Luigi's Mansion 3)

The Rooftop is the highest point of The Last Resort in Luigi's Mansion 3. The final battle against King Boo takes place here. The Virtual Boo has no map for the Rooftop or the stairway leading up to it; it simply displays Luigi's location as "???". This area is only referred to by name on the file selection screen.

After Luigi (alongside Mario) frees Princess Peach with his Dark-Light Device, they have a brief reunion; only to be interrupted by King Boo appearing behind them. He is surprised that Luigi has made it this far and angered that he should have run away. King Boo attempts to trap everyone including Professor E. Gadd and three Toads into one big frame; he successfully captures everyone except Luigi, who was saved by Polterpup. King Boo is even more angered that he did not capture Luigi and decides to have a battle with him.

Battle
King Boo can summon lightning onto many squares that shines purple light; Luigi must avoid this by going to an area that doesn't shine purple light. He can also swing his tongue; Luigi must use Burst to dodge the attack. King Boo then throws out bombs which Luigi must launch him back into his mouth; after he explodes, Luigi and Gooigi must work together to slam King Boo a few times.

In his second phase; King Boo summons a fake version of himself lacking any front teeth; Luigi must launch a bomb back into the real King Boo.

In his final phase; King Boo makes the frame much larger, thus giving Luigi four minutes to defeat him. King Boo summons two fake versions of himself; once again Luigi must launch a bomb back into the real King Boo. After Luigi and Gooigi slammed King Boo a final time, he is sucked into the Poltergust G-00 and releasing his Gem Crown.