Metallia

Metallia is the force behind Queen Beryl. She's the one who attacked the Moon Palace during the Silver Millennium. She possesses Beryl's body in order for Beryl to be stronger to fight Sailor Moon, but it didn't work and both Beryl and Metallia were destroyed.

Queen Beryl

Beryl was once a servant of Prince Endymion's during the Silver Millennium, she turned evil from Metallia's influence.

The 4 generals were in fact Prince Endymion's 4 generals. They ended up Queen Beryl's generals.

Jadeite was the first general. He was imprisoned in ice in the anime. In the manga he was killed by Sailor Mars.

Jadeite/Jedite

Sailor Mars was Jadeite's lover in the Silver Millennium.

Nephrite was the 2nd general. He was killed by Zoicite in the anime. In the manga he was killed by Sailor Jupiter.

Nephrite/Neflite

Sailor Jupiter was Nephrite's lover in the Silver Millennium.

Zoicite was the 3rd general. (S)He was killed by Queen Beryl in the anime. In the manga he was killed by Sailor Venus.

Zoicite/Zoicite

Sailor Mercury was Zoicite's lover in the Silver Millennium.

Kunzite was the last and most powerful general. He was killed by Sailor Moon in the anime. In the manga he was killed by all of the scouts(Sailor Planet Attack).

Kunzite/Malachite

Sailor Venus was Kunzite's lover in the Silver Millennium.