There is no way to remove the visual effect, AFAIK.
From the
Dragon Knight Saga FAQ/GuidePath (Blue Moon):
-Return to the first floor, and head up the stairs to the second. Go east and
find a large bedroom.
-Put on the HOS, and look for a lever in the corner directly south of the
entrance. Pull it, then head to the center of the room. Take off the HOS.
-Jump on the bed with a canpoy over it, and then to the platforms that
appeared. On the top one, there is the Blue Moon, the first of five orbs.
(get Blue Moon)
Path (Violet Blast):
-Return to the main room, then head along the west path on the second floor.
-Before entering the doorway at the south end of this balcony, look out over
the first floor. A glowing blue path of light should lead out and up over
the foyer. Follow it to the top, and claim the Violet Blast. (get Violet
Blast).
Path (Fire God):
-Return to the balcony and head through the doorway. Turn right into the
library. Stand on the pressure plates in the following order: southwest,
northwest, southeast (requires HOS), northeast.
-If for some reason you want to take the HOS off before stepping on the final
pressure plate, the southeastern one will stay pressed even without the HOS,
although visually it won't look like it's still active.
-This will make the Fire God appear on the desk. Take it. (get Fire God)
Path (White Snow):
-Head into the room opposite the library in the western wing. Put on the HOS
and pull the levers next to each colored torch along the east wall. This
changes the colors.
-The north torch should be green, the middle one blue, and the south one red.
-This places the White Snow on the altar to the west. Claim it. (get White
Snow)
-For some reason, the HOS is automatically unequipped after setting the
torches correctly. Weird.
Path (Moss Rat):
-Return to the first floor of the academy, then put on the HOS and look to the
west. What was previously a walled-in doorway is now open! Head down into the
dungeon.
-Take the HOS off and head across the planks along the north side of the chasm
in the center of the room. When you reach the locked door, turn around.
-Put the HOS on, jump on the glowing platform, then onto a piece of rock on
the north wall.
-Take the HOS off, and jump along the platforms that are only visible without
the helmet. Jump to another piece of rock on the north wall after the third
platform.
-Put the HOS on once more, and jump across the glowing platforms to a ledge on
the south wall.
-Take the HOS off, and jump up the two visible platforms. Claim the Moss Rat
from the cage. (get Moss Rat)
Path (Antediluvean Vault):
-With all five orbs, head to the bottom of the chasm in the hidden basement,
where the Moss Rat orb was.
-Place the five orbs on the correct runes (Orbs removed as placed):
A: Fire God on the Snake rune.
B: Blue Moon on the Shield rune.
C: Violet Blast on the Gold rune.
D: Moss Rat on the Death rune.
E: White Snow on the Mountain rune.
-The Antediluvean Vault will unlock once the orbs are placed. Enter when you
are ready.
