Well, that certainly depends on the context. By their very nature, they are all awful in their own rights.
Azura? Enslaves her followers. Traps them in a null sense of peace and tranquility. She disguises her shackles with love. Much like a heavily over-controlling parent. She masks her true intentions with the idea that “she knows best”. The moment you try to defy her though, just like those parents, she will strike you.
Boethiah? Only cares for bloodshed and battle. She will lie, she will cheat, and she will manipulate both her followers and those who are against her in order to cause as much chaos as possible. Boethiah would, quite literally, kick a man while he is down to “test his mettle”.
Clavicus Vile? Is nothing more than a nuisance, and that is on purpose. His eternal struggle is one of boredom. He views the world as a stage and he will pluck and prod the actors as much as he wishes. Not to mention his other half, his companion Barbas, who often causes even more trouble.
Hermaeus Mora? Perhaps he could be viewed as one of the “least awful” simply because he doesn’t involve himself often. He spends his time hunting knowledge, striving for the unobtainable, but never quite comprehending it. He takes the time to hoard information, to hoard knowledge both forbidden and not, but does not take the time to fully comprehend it. Knowledge is power, but he’ll never obtain that power for his lack of true knowledge.
Hircine? Could be another one viewed as the “least awful” for similar reasons. Hircine does not go out of his way to be worshiped, nor does he seem to truly wish to be. He finds his thrill in the hunt, however, only when it is fair. I would go as far to say that Hircine has some sense of honor.
Jyggalag? Though not currently his own prince, he will return eventually. Or perhaps he already has, and is simply floating out in the infinite beyond? No one can truly say. I would say that Jyggalag has the potential to be one of the worst, in the sense that he’s extremely radical in his beliefs. Wisdom and Order, at any costs. He would deny the very nature of mortality by forcing all to follow a totally predetermined plan. Suck the very life out of all around him until everything was gray.
Malacath? Is certainly not the brightest of his brothers, but I would give him this, he certainly cares about those who follow him. His very nature is that of being an almost fatherly figure to those who have been beaten down and broken. Though his focus on battle, his thirst for bloodshed, certainly disqualifies him from being one of the least awful.
Mehrunes Dagon? He is a being of chaos, even more so than many of the other Princes. He brings about destruction, disaster, and death in his wake. Though, he also brings about change. It is his field in which revolution, both good and bad, come forth. He appreciates the ambitious, and could very well represent the turbulent energy below our feet.
Mephala, my Anticipation? She is quite similar to Vile in the sense that her only goal is her own amusement. They will spend countless centuries spinning a web, trying to cause the most “interesting” outcome. Patience is a natural part of her own sphere, and she would wait an eternity if it meant seeing things play out as she wishes. Though they often do not. Though talented, yes, she views all mortals as puppets on strings. And once she is bored of you? She will toss you aside.
Meridia? Well to put it simply, she is similar to Jyggalag in the sense that she is incredibly radical in her own beliefs. There is also a similarity to be drawn between her and Mora, that being an incredible sense of greed. She is insatiable her quest for “light”. Out of all of the princes, she is one of the ones which demand worship the most. She is practically starved for praise, and will burn anyone who says anything negative about herself. Then one can draw a comparison to Azura. She views mortals as ends to a means, as pawns which she can use. Meridia may lie, she may say that she cares for you, and that she is a light in the darkness. But a light that burns bright enough to blind you will only cause you to see eternal darkness.
Is Molag Bal even worth speaking about in this context? He carries all of the negative traits of his brothers and sisters. Cunning in his schemes, patient to wait for them to come to fruition, greedy in his quest for power and dominance, cruel in his thirst for bloodshed, and completely uncaring for his followers. Though perhaps his worst trait is his own pride, which is always his own downfall. Whether it is at my own hands, or that of the many mortals that have and will defeat him for eras to come.
Namira is gross. That is her very nature. She does not WANT to be viewed as anything other than awful. She revels in her own repulsion, and the deeds which would cause people to pluck out their own eyeballs in order to not see them again. She is quite like Azura and Meridia in the sense that she only cares for the worship of her mortals. She sees her worshipers more as toys than anything else. Namira simply wants to see how far she can bend a person until they break. How long they can hold onto themselves before they simply become a part of her.
Nocturnal? Well, to put it simply, she is a bitch. Just as prideful as Molag Bal, while also viewing herself as superior to the others as Meridia. She believes herself to be “unfathomable” and gives herself her own titles as she sees fit. She pushes those that follow her to be as selfish as she is. To seek their own power and ambitions, at any cost. While also chastising them when they defy her, despite her own teachings of treachery. Nocturnal’s very nature of being “shadowy” and “deceiving” is often what causes her to be so predictable in the first place.
Peryite, one of the most forgotten princes, revels in the suffering of others. He views illnesses, blights, diseases as being gifts which he blesses the mortal plane with. All he cares for is systematic destruction, a controlled pandemic, something which he can sit back and watch the numbers rise for. He is methodical, and will often try to stay a step ahead of those he is against. Many underestimate this dragon, but I believe that is simply part of his own plans.
Sanguine, I’ve found, is often viewed as one of the “better” Daedra by those of you on the web. And indeed, there are mortals in our realm as well who simply view him as a “party god”. That is by his own design. He represents that feeling of excitement as you first take a sip of alcohol. One? It can not hurt. Two? What could go wrong? Three? Four? Then it goes on, and on, until it spirals out of control. THAT is what Sanguine is. The destruction of one’s self, by your own hands. He pushes mortals down an ever darkening path, until they can no longer recognize themselves. That is the nature of the prince of debauchery.
We’re nearing the end now, are we not?
Sheogorath..Is a Prince in which I’ve had many dealings with over the years. The Mad God, the Patron of Art, the Gentleman with a Cane, the Tester of the Mind. He is many things, and yet, he is all simply Sheogorath. Of all the princes, he is the only one which is truly unpredictable. In some ways, he is similar to Sanguine, in that he’d rather allow someone to destroy themselves than to do it himself. Just like the others, his main goal is often to sate his own eternal boredom. The difference is just that he is far more creative in his means to do so. One day? He might save a little kitten so he might watch it grow. The next day? He might rip out its entrails to jump rope with. Sheogorath simply DOES. Planning is something he leaves to others, though sometimes, for the sake of being unpredictable, he might plan himself. That is ultimately how I view Sheogorath. Not good, or evil. Not nice, or awful. He is simply unpredictable, the truest being of chaos there is. Of all of the Princes, Sheogorath might just be the one with the most potential.
Lastly, we reach Vaermina. She simply hungers for destruction, and will often give people flashes of future disasters, only for them to cause those disasters sooner. She views mortals as being in which she can torture eternally, whether they are awake or sleeping, she claims them either way. She will take your worst fears, and make you face them over and over until you are no longer afraid of them. Then? She will simply find something new for you to fear. Until the only thing you fear is yourself, and you take your own life. Only for you to wake again. Vaermina is a Prince of eternal torture. Nothing more, nothing less.
There is no “least” awful Daedric Prince. They’re all awful in their own ways. Hermaeus Mora and Hircine might be the least destructive of them, but even then that is a stretch. The Daedric Princes are by their own nature, destructive. Wherever they might go they bring about some kind of change. Sometimes positive, sometimes negative. Regardless of who they might be. Comparing their individual actions is fruitless, as they are constantly at work in the background. Likely with an infinite number of unattributed events being caused by themselves. That is my final stance on the matter.