Prelude: Sometime ago, I reported to my GM that /effect does not switch off the visual effects on Blindness as it should be on official servers. His reply was simply, "Its a client related thing. Nothing we can do about it."
Well, he was correct. If the GM is unable to do anything about it, then it's up to you to fix the bug and edit the client side.

[youtube=425,350]MVkFYF1HEvg[/youtube]
This edit will remove the
visual effects of Blindness from:
- Demon of the Sun, Moon and Stars (a Star Gladiator skill which causes permanent reduction in visibility)
- Wall of Fog
- Blind Attack/Darkness Attack (from Anubis, Marc, Familiar, etc..)
- Blind Status (Familiar cards)
1. Download and install the necessary programs below.
Download Free RAR Extract Frog2. Download the necessary files (fullb.tga and white02.bmp) from any of the following
uploading.com (Mirror 1)
Rapidshare (Mirror 2)
How to Download from uploading.comClick on the link provided above. Then click on "Download file"

After the countdown has finished, click on "Download file" to proceed

Click on "Download file" again and then Save File

3.
IMPORTANT Create the following folder:
C:\Program Files\Ragray\data\texture\effect\
4. Copy the extracted files and paste them in the newly created folder.

(As you can see, both files are blank "hot pink" images. The color "hot pink" (Red: 255 Green: 0 Blue: 255) will appear transparent in game. Thus, we are editing the client to show the visual effects of blindness as "transparent" instead of the normal black/darkness)
5. FINITO – Just load RO, and you will be immune to the
visual effects of Blind on your screen only. When affected by Blind status, your HIT and FLEE rate will continue to be reduced by 25%; however your range of visibility will not be affected due to the modification.
TROUBLESHOOTINGClick hereIf you are from a TYPE III Server. I pre-made blind.grf which can be downloaded from
here. Simply edit your data.ini file and ensure that blind.grf takes priority over other grfs.
DISCLAIMER:Please check with your server if you are allowed to edit the client side. Some servers prohibit that.
It appears, this edit might disable the "visual timer effects" indicator shown next to the effects icons found on the top right of the screen on some servers.