In Revelations 19 where the Beast and Kings of the Earth. They fought against the rider on the white horse(Christ) and lost. The Beast and false prophet were thrown alive into the lake of fire

Source: Revelations 19:19

In Revelations there is a war between two groups of angels. Who are the opposing commanders?

Michael the archangel fought the dragon also known as Satan. Satan’s forces lost and were removed from heaven. However they were released on the earth.

Source: Revelations 12:7-9

Peter is referring to fleshly lusts. These war against our souls and seek to lead us to sin.

Source: 1^st Peter 2:11

Peter says these war against our soul. What is Peter referring to?

According to Paul what is different about warfare for a christian?

As Christians our warfare is spiritual rather than physical. It is internal rather than external warfare.

Source: 2^nd Corinthians 10:3-7

Jesus spoke of wars at the beginning of the end times. How many Gospel(s) record this?

All the synoptic gospels Matthew, Mark and Luke. Record this saying which happened at the beginning of Holy Week

Source: Matthew 24:6, Mark 13:7, Luke 21:9

According to Jesus what do Kings do before entering into war with another King?