Suicidal

Villains who have either attempted to take their own lives, whether they have succeeded in doing so or been overly eager/bold in the face of death. There can be several different reasons for this including remorse, honor, knowledge of worse fates, despair, a greater cause, insanity, nihilism, taking others with them, villainous martyrdom or even redemption. Some of these villains might even be kamikazes, as they may attempt to bring down someone else with them (such as the hero), whether this means actually killing them or simply doing something such as bringing down their reputation.

Some of these suicidal villains didn't necessarily directly cause their suicides (whether attempted or successful) and were simply eager or bold in the face of death. This includes villains who, when faced with a potentially fatal issue (such as a medical emergency), they didn't do anything to save themselves. In some cases, they might have even attempted to make the issue worse.