An option that causes the game to show you a test screen before going into character selection options. This test screen should have your default terminal background and show monsters of every possible color, so you can see if any particular color is unreadable on the background (dark blue and dark gray are common culprits for this) and adjust your settings as necessary.

Since the encyclopedia entry on psuedodragons says they change color to blend in with their surroundings, they should do this in the game too: whatever color the walls of the branch are, psuedodragons should be that color.

When hallucinating, randomize dragons’ colors and glyphs among all dragon colors/glyphs, and allow messages about them to use hallucinatory colors, e.g. “The mottled dragon bites!”

Chromatic light, whose explosion attack causes you to see all monsters in random or consistently incorrect colors for a while.

Assign a different color to the Arch Priest so that he doesn’t appear identically to all the quest guardians milling around in the area.

Color priests differently to distinguish them from player monsters.