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Blue Blazes are blue normal ghosts encountered in Luigi's Mansion. They are Blue Twirlers with water protecting their thirty-HP hearts. They are normally found only in the Safari Room, in the east wing of the third floor of the mansion, although one is encountered in the Tea Room during the blackout. The Blue Blaze has a massive earthquake attack that costs Luigi ten HP, as with its non-elemental counterpart. In order to reveal its heart, Luigi needs to blast it with ice. Being weakened by ice, it completes the triangular Elemental Medal relationship also found with the Temper Terror and Flash. In the Safari Room, the Blue Blazes appear when Luigi shakes the middle deer head, along with two Garbage Can Ghosts. In the Tea Room during the Blackout, a Blue Blaze appears in the center of the room.
In a piece of pre-release footage, there are three Blue Blazes playing poker; though the cutscene itself isn't in the final game, they make a short cameo in the form of a screenshot in a texture in the scene when Mario is being turned back to normal.