Not to be confused with magic contamination, which was once simply called glow.
In Crawl, there are several things that can make your character glow. The only effect that glowing itself has is to negate any source of invisibility; however, glowing is caused by sources that are usually somewhat dangerous in and of themselves:
- Magic contamination (yellow or higher): This is the most dangerous, as it will very likely leave you with some bad mutations as it decays. You can disperse it more quickly by drinking a potion of cancellation.
- Corona: This monster spell makes you easier to hit, in addition to negating invisibility. It's rarely ever an issue, as only gnoll shamans, fauns, Dowan, Kirke, and some player ghosts can cast the spell, but weak Charms and Hexes miscast effects may apply it to you as well. It can be resisted via magic resistance.
- Sticky flame: This causes fire damage over time that can be resisted with fire resistance. The effect itself is irresistible except through becoming insubstantial (only available through rare transformations), but you can put yourself out by jumping into water or using a phial of floods.
- Halo: Standing in the halo of a holy monster (or your own halo, if you follow The Shining One or wield the artefact morningstar "Eos") will cause you to glow as though you were affected by Corona.