The Red Horse of the Apocalypse (War)

Rev.6:4 And there went out another horse that was red: and power was given to him that sat thereon to take peace from the earth, and that they should kill one another: and there was given unto him a great sword.

The Black Horse of the Apocalypse (Famine and Inflation)

Rev 4:5 I beheld, and lo a black horse; and he that sat on him had a pair of balances in his hand. And I heard a voice in the midst of the four beasts say, a measure of wheat for a penny, and three measures of barley for a penny; and see thou hurt not the oil and the wine.

The Pale Horse of the Apocalypse

Rev 4:8 And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.

The 5th Angel (Biological Warfare perhaps?)

Rev 9 And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit. And he opened the bottomless pit; and there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit. And there came out of the smoke locusts upon the earth, and unto them was given power, as the scorpions of the earth have power....and the shapes of the locusts were like unto horses prepared unto battle; and on their heads were as it were crowns like gold, and there faces were as the faces of men....

Angel standing in the sun (Armageddon)

Rev 19:17 And I saw an angel standing in the sun; and he cried with a loud voice, saying to all the fowls that fly in the midst of heaven, come and gather yourselves together unto the supper of the great God: that ye may eat the flesh of kings, and the flesh of captains, and the flesh of mighty men, and the flesh of horses, and of them that sit on them, and the flesh of all men, both free and bond, both small and great.