What is a word with prefix of doom?

There isn't a common English word with the prefix "doom" in the way you're thinking.

However, the closest we get is with the suffix "-doom", which does imply a sense of ill fate or destruction. Some examples are:

* World-doom: A word coined to describe the potential end of the world.

* Blood-doom: A similar invented word for the potential of a bloodbath.

While "doom" is often used as a prefix in fantasy or sci-fi settings to create words like "doombringer" or "doomstone," it's not a standard prefix in the English language.