Part II of Part 7 Engagement in Warfare in these last days.

You must know him, know his nams and chararacter to engage weapons against him. 

Revelation 9:11

a destroying angel, The accuser of our brethren

Revelation 12 against one in the assembly, i.e. a complaintant at law; specially, Satan

The adversary

I Peter 5:8

an opponent (in a lawsuit); specially, Satan (as the arch-enemy)

Apollyon      

Revelation 9:11       

a destroyer (i.e. Satan) 

Beelzebub     

Matthew 12:24 Mark 3:22 Luke 11:15 dung-god; Beelzebul, a name of Satan