Not Satan, but speaks on behalf of Satan. The second beast (the false prophet) and the first beast (the person) are going to be cast alive into the lake of fire, at Jesus's return. Differently, Satan is going to be cast into the bottomless pit.
The "another beast", a 2nd beast described in Rev.13, is about a singular entity, a person, the coming Antichrist-false Messiah.
It's about the same one of Matthew 24:23-26 that is to work the great signs and wonders in Jerusalem for the end which Lord Jesus warned us about in His Olivet discourse (we're supposed to remember what we studied before). He was warning of the coming Antichrist as
'a spurious Messiah' (Dr. James Strong's definition of "false Christs"). That is what the Rev.13:11-14 verses shows him doing, along with setting up an idol abomination in false worship like the king of Babylon did in Daniel's day. That "another beast" is about the "man of sin" that Apostle Paul warned of in 2 Thessalonians 2:1-9. All those Bible descriptions about a false one at the end of this world is about the same one, Satan himself when he is booted out of the heavenly down to our earth, with his angels, at the end of this world.
The concept that this is about the "false prophet" of Rev.16 and 19 is a leaven fragment from men, i.e., incomplete fragmented understanding.
The "false prophet" and "beast" that go into the "lake of fire" at Jesus' coming show those are only ROLES that Satan as Antichrist will play. The reason is because ONLY Satan and his angels are already judged and sentenced to perish in the future lake of fire, that fire especially having been prepared for him (Matthew 25:41). No flesh man has been judged yet today, not even Judas, even though we may think he is doomed.
That decision who perishes is not ours, but Christ's only, and He has yet to make that decision for anyone born in the flesh. So because the false prophet and beast go into the lake of fire before the Judgement, that means those cannot mean flesh men. They are only character roles that Satan as that "another beast" will play. The most important point to grasp about the "another beast" then is how it is pointing directly to Satan himself coming to work signs and miracles to deceive the whole world with, just like the Rev.13:4-8 working also shows about the "dragon". And it does say the whole world (excepting Christ's elect) will worship the "dragon". And per Rev.12:9 the "dragon" we are told is but another one of Satan's many titles. And the "beast" title is also applied to Satan in Scripture like Rev.11:7 and Rev.17:8, etc.
You should go to Ezekiel 28:16-19 and you can see why the second beast is not Satan.
I have studied the whole Book of Ezekiel, and the Ezek.28 & 31 chapters several times over. And that does not prove that Satan is not the "another beast" of Rev.13:11.
What Ezekiel 28 shows with using the flesh king and prince of Tyrus, is God uses them as 'types' for Satan in the world before this one when Satan was originally 'perfect in his ways' as a covering cherub with serving God, and then he rebelled against God. The Ezekiel 31 chapter, which goes with that kind of parable in Ezek.28 further describes that time before Satan rebelled using the idea of the high tree and trees in God's Garden, God using the Assyrian and Pharaoh as types for Satan like He did in Ezek.28 with the king and prince of Tyrus (means 'rock' by the way, the false "rock" of Deuteronomy 32:31, which is a direct pointer to Satan in contrast to the True "Rock", our Heavenly Father).
When Jesus returns, there will be the beast (the first beast), and the false prophet (the second beast), and the living, speaking, image of the first beast on the temple mount grounds.
I know some brethren like that slogan of the 'unholy trinity' with that idea, but that's simply not written in God's Word. It's an idea started by Satan's host, for they love to create little slogans and advertising phrases to deceive with.
Again, the "false prophet" and "beast" of Rev.16 & 19 are simply ROLES applied to Satan's coming working as the "another beast", a 2nd beast, working great signs and miracles, raining fire down from heaven in the sight of men to deceive. The "image of the beast" will most likely involve a TV video image of the idol in Jerusalem, for that definitely in Jesus' day would be how they would see a working television 2,000 years ago. In Rev.11 when God's two witnesses are killed, it is shown there that the nations will 'see' their dead bodies left laying in the street. How will the world see that? That event reveals it could not come to pass until we had satellite technology. Everyone's got a cell phone today, even in the middle east.
