If you delete the shades file in the data folder of Ultima Underworld I or 2, the game world will always be at the fullest brightness. No need for light sources. At least this worked with the original releases back in the day. Remember to back up the shades file.

In ultima underworld 2 if you throw a potion at a wall you wil get a reusable pile of rubble that has the same power as the potion

thanks for the info

Rather than deleting it, just rename it. ("Shadez.dat" or the like.)

You can use the same glitch in Ultima Underworld 1, but you will have to cast the Fireball spell at them to turn them into rubble because throwing them against a wall doesn't damage them.

Remember using the shades file cheat when playing the original game but I can not find it in the GOG version anyone know if it is still possible to use it at all ?

I can see in my Mac version. I think I know wht's going on: In you installation there should be an image file somewhere that contains the contents of the game's disc (as it was originally shipped). I don't know the name of the image file, but the Shades file is on the disc, so you would need to mount the image somehow and then remove/rename the file. How? I don't know.

Many thanks for that info. After fiddling around with trying to extract/repackage the game.gog iso file (game stopped working when I did this) I edited the game.gog file using poweriso (free editor found online) didn't need to rename just choose show all files open game.gog and find the shades file then remove it and click save. Now up and running with full brightness. Hope this will help any others who had same problem.