(Alert, enormous paragraph in approach, you've been warned). Something not tier related but interesting to note in-game, wich (for me) confirms Mohg is not only the most evil character but also the most dangerous character in the game. Why? Because he's the only one whose forces and power aren't on the decline. I mean, think about it for a second.
All the minor descendants of Marika (plus Godwyn) have been assassinated. Godrick is a pathetic excuse of a lord whose fiefdom is really just a ruined castle and his army is a bunch of traitors and criminals who can't even really impose order over Limgrave. Rennala, once the greatest sorceress in the LB, is a shell of her former self and so insane we're not even sure she's still aware of her surroundings and the Academy has locked itself to avoid contact with the outside world (not to mention the mages of the Academy being a group of sociopathic mad scientists and megalomaniacs performing experiments that would make the Mage's Association from Fate blush). Radahn had been reduced to a mindless animal who eats corpses of foes and allies alike and whose only shred of humanity left is for his horse and his Redmanes have either become ghosts eternally fighting or crazy survivalists trying to contain the Scarlet Rot at all costs. Ranni can't do anything until Radahn is dead and barely has any resources left. Morgott's fiefdom of Leyndell, while still relatively in good shape, is falling apart because he refuses to help fixing things. Malenia is comatose after blooming against Radahn and her soldiers are literally rotting away and confined to the borders of the Haligtree, wich is itself slowly rotting ever since Mohg kidnapped Miquella. Heck, even smaller-scale similary evil or dangerous people can't really do anything. Seluvis is too obviously evil for anyone to trust him and has lower (disturbing) objectives, the Dung Eater is trapped under Leyndell, needs someone to bring him his seeds to create his rune (and has to assume whoever helped him will follow through his plan after he dies), has no army at his disposal and can become one of Seluvis's puppets, Sellen is trapped and forced to astral project herself to communicate with the outside world and Gowry needs someone outside of him to manipulate Millicent who is fully refusing to bloom and won't unless you betray her.
Now take Mohg. Instead of losing underlings, he is actively adding to his forces, with willing followers that are Tarnished Bloody Fingers and Sanguine Nobles who are all very skilled at using blood Magic and overall very capable, plus potentially the player through pvp since he's literally the origin of pvp in the game. He has experimented on and corrupted countless Albinaurics who now obey him and are much stronger and faster than their normal kind and has blood zombies, dogs, giant crows at his disposal, all ready to be unleashed whenever he wants. His fiefdom is a castle that is extremely well-hidden and difficult to reach (unless you go through Varré's quest and even then, that means you will help Mohg), the only way being a portal in the Consecrated Snowfields, a very late-game area, and since he literally created Blood Incantations in the game, his influence is ridiculously spreading since even people who are not necessarily affiliated with him actually use his powers. And because his cult is growing, his own power is growing to since he gains strength from performing sacrifices for the Formless Mother. Also, since his castle is so difficult to reach, it's entirely possible to complete the game without finding him. This means that, no matter the ending, you've got one gigantic problem growing stronger until he's ready to unleash his power onto the LB and you have far fewer Tarnished to help this time (and the remaining demigods if you have not killed them all won't necessarily be able to defeat him in their current state and even the SR could be defeated by the FM with all the power Mohg has been gathering for the Formless Mother).
You know the worst? The only other demigod who has any shot at opposing Mohg...is Rykard. Yes, he has no army anymore (outside of the abominations he unleashed during the Siege) and his territory is very limited but he's still adding to his forces by recruiting Tarnished to help him and when he's not, he's devouring them to gain more strength.
So basically, the only two demigods who are genuinely growing in strength are a sadistic incestuous (and pedophile) blood cultist who experimented on various creatures to turn them into insane followers performing blood sacrifices in the name of a ********* Outer Goddess and a mass murderer and tortioner who willingly fed himself to an abomination to become a cannibalistic horror and intends to grow strong enough to devour the Gods and ultimately the whole world. Says something about how much of a shithole the situation is when the game tells you that the DUNG EATER is a better option than these two.
