Queen Metalia:
Queen Metalia is never seen in the anime until she takes over Queen Beryl's body. Se is one of the essences of chaos that broke up and took form in different head villains. She is the ruler of the first season, and she governs it all. You have to plead with her for her to even talk to you. She almost got fed up with Queen Beryl at the end but then she got the idea to team up and share bodies. But, Sailor Moon was too powerful, and her good crystal completely destroyed Queen Beryl, giving the chaos no where to go, except back to Sailor Galaxia. You don't really see her much, so not much is know of her.
Queen Beryl:
Queen Beryl is the misunderstood head henchmen of the Negaverse. She was originally a priest type person on the Moon Kingdom, and she had , excuse my language, one HELL of a crush or Prince Endymon. She secretly loved him, but she wasn't a Princess, and she didn't have enough courage to talk to him, but one day she changed her mind, and she was going to confess her love. She was very happy, and when she got to Prince Endymon's chamber she saw him and that moon-brat kissing and declaring their love. Well, if she couldn't have him then no one can! So she made a deal with Chaos, and she became Queen Beryl, bent on the destruction of the Moon Kingdom, just because the stupid moonbrat got her man. So when they were sent to Earth, they needed to gain power, and get henchmen, so they did and then she staged her energy attack. And when they got enough energy, she would release the dark forces, turning the world hers.
Jeidite:
He is the first henchman of the nega-force. He is pretty weak compared to later badguys, but he was one big challange to the senshi that were just getting together, and learning teamwork. He tried and tried to get energy, but wherever he went, the sailor senshi always seemed to find him! He tired and failed many times, and Queen Beryl got fed up. She put him in icey stuff, and sent him away, giving room for the next of the more powerful henchmen. In the manga he was destroyed by one of the sailor senshi.
Nephlite/ Nephrite:
Nephrite was the second of the head henchmen. He used the stars to govern which person he would attack for energy next, which was a good idea because he would get maximum energy from one person, exept for one thing. Those dratted sailor senshi just happened to in some way, know all of poor Nephrites targets. He was not at all succesful, and then he met Molly. He actually gave up the evil so he could be with her, and everything seemed perfect, but then Zoicite made a mistake, and he thought that Nephrite had the ginzuishou, and she attacked him, and injured him fatally. Molly was devastated, but it didn't even phase Zoi! I don't know the exact death of Nephlite in the manga.
Zoicite:
Now I think Zoicite was done the greatest injustice of all the bad guys in all of the anime series. In the anime, Zoicite was made into a female, and he was originally a male, so I will refer to him as a male. I guess his relationship to Kunzite was bad or something. Zoicite was the third of the negaforce henchmen, and he was the first one to look for the rainbow crystals. He got a few and lost a few, but Beryl wanted them all. So Zoi made a deal with Tuxedo Kamen that they would meet together and battle for the others share of rainbow crystals, but Zoi double crossed poor Tuxy, and Kunzite took all of the rainbow crystals. Zoi also got double crossed, and Sailor Moon was there with them during the battle. Tuxy got hurt very badly, and Sailor Moon was devastated, and she shed one tear, and with that tear the ginzuishou. Then later Zoi was killed because of his insolence to Queen Beryl.
Malakite/ Kunzite:
Kunzite was the last of the head henchmen, and was seen during Zoi's reign. He was the most powerful, and the most conceited. His main job was to recover the ginzuishou, but then Queen Beryl corrupted Mamoru, and then his job was babysitting. He wasn't at all happy about that, and got blamed for all of Mamoru's mistakes. He almost got the ginzuishou, but it dissapeared, aww too bad. Sailor Moon destroyed him with the power of the crystal he sought after so long, and with his death he was able to go back to his love Zoicite.