Plus, we have to consider the Dark Wizard, who is certainly a much bigger threat than Adar. Icecreamdif kinda? I wouldn't say Sauron's "Pure Evil", because in his mind, he's doing the right thing.
I will say this, TRoP has sparked people's imaginations... since Adar and the Dark Wizard (from what we know so far) were invented, only the inventor can tell us who is more powerful. Right now, I don't see how you can say the Dark Wizard is certainly a much bigger threat than Adar, but I guess it is an opinion. An explanation would be nice.
@Guy who types stuff 1.1 "strongest" does not equal the same as threat. Radagast was probably stronger than many antagonists in Middle-earth, but he didn't do much.
The Easterlings were some of the strongest warriors of Arda during both the 2nd and 3rd age. While the Orcs are strong and good fighters, Easterlings are faster and more intelligent. The Dark Wizard is a Istar, and seemingly a very strong one. Tom Bombadil also said Dark Wizard controls much of Rhûn, aka Asia.
^ This seems off topic. Also, it sounds like you're basing an invented character on the strength of a larger group that he hasn't been shown to have a strong relationship with.
The Easterlings strength is also dubious... for all we know they just had large numbers, aggressive tactics, willing to sacrifice many lives, and the help of Morgoth and Sauron.
