The third role that Paul describes in Ephesians 6:12 is the spiritual powers of evil. These are the ordinary spirits that do the dirty work of the Cosmos Dominators and Government-Spirits that control them.
Ordinary evil spirits mostly work by putting thoughts and ideas in the mind of a person and stirring up their desires. They can also effect changes in their physical bodies, mostly sickness. They can make a person exhausted or tired.
When an evil spirit gains control of the persons will, it enables them to control a person's choices and manipulate their body.
Some spirits prefer to remain detached. They can then move from person to person and have a go at them all at the same time. A deceiving spirit might find this a convenient way to operate because they could deceive a group of people moving around them and planting the same lie in them all, so they are deceived together.
Evil spirits can move from person to person. They are always looking for an opportunity to do greater evil, so if they see a better opportunity in another person, they will take it, and enter them. Of course, if they have control of a person's mind, they may be reluctant to leave, because they do not know if they will be able to get control of a new person. There are benefits for them in having control, but they are free to go to another person, if they think they can benefit.
In principle, a person can deliver him/herself if they renounce the spirit and command it to leave in Jesus' name. However, it is really hard to do on your own, especially if the spirit has control of your will. It can give thoughts that confuse its victim, making it hard for them to resist it. That is why it is often better to have two or three people praying against the evil spirit.
Jesus promised that there is greater authority when two or three are praying together. However, the key to deliverance is the victim renouncing the right of the spirit to be there. Once the evil spirit loses the authority that they have over their victim, they have to go. Of course, they will try to get their place of authority back by tempting the person to fall into sin again, so it is good to have other people praying for the victim and encouraging and supporting them.
Similar Powers but Different Roles
I think that evil spirits are mostly the same as each other. When they were created, they were all the same, and there was no hierarchy amongst them, but after the fall, they established roles and a hierarchy to go with it. They get a role when they discover a particular way of operating. Some spirits developed a skill at promoting a particular sin, so that gives them a name. Others get a place in the hierarchy of spirits that gives them additional power and authority. This place establishes their role.
Angels and evil spirits are followers. They listen to the closest voice and do what they are asked to do. Without the wisdom of the Holy Spirit, evil spirits are cut off from the wisdom that angels need to operate effectively. The Holy Spirit ensured that they worked together in unity. Cut off from his wisdom, evil spirits fall into disunity and struggle to escape it. They only way that can avoid disunity and confusion is by forming hierarchies and allowing themselves to be bullied by the spirit that leads the hierarchy.
These groups and hierarchies are always fluid, because spirits are always rebelling against their leaders and trying to take their place.
Government-spirits
Government-spirits are often called "principalities and powers", but those names do not explain much, so I prefer to call them what they are. A Government-Spirit controls the leaders of a city or nation. It get controls by leading a group of spirits that work in the hearts and minds of the leaders. These spirits would include spirits of pride, control, love of power, anger, etc. They submit to the government-spirit for the benefit of getting to manipulate a nation. This gives the government-spirit great power.
A government-spirit leads a gang of spirits and uses them to control the political leaders of a nation or city. They will use whatever will work with the particular leaders they are trying to control. Spirits encouraging pride, love of power, control, hatred, anger and deception will often be part of the gang.
When a government-spirit is spiritually defeated, it will keep on trying to be a government-spirit without any success, because it has lost the supporters who made it powerful. It will mope around talking about its past glories, but totally confused about how it might get its power back. This forlorn spirit will become powerless and feeble.
Cosmos Dominators
Evil spirits form gangs with a leader who is the most ruthless rising to the top. This leader looks for opportunities for the gang to do its evil work. It becomes their leader because it is the most ruthless and effective at destroying God's world. Once spirits join his gang, they are afraid to leave because the leader is so ruthless and violent. The Cosmos Dominator looks for opportunities for his gang to do its stuff. Whenever there is evil stuff going down, they will be there. They enjoy murder and every kind of destruction that they can think of.
Some evil spirits commit to following a Cosmos Dominator, because it offers them opportunities to enhance their power. He uses violence and power to keep them in line. If one tries to pull out of an alliance, the Cosmos Dominator would set other spirits against it. Of course, if they all rebel against his leadership, he would be powerless to keep them in line.
These powerful spirits are all using stolen authority, so they are always vulnerable because their power over others depends on them being more evil, or more clever than those they control. Other spirits will always be stepping up to have a go against them. This is why the spirits in control have changed throughout history. Satan (Accuser) has had times on top, but Death and Destruction have been on top at other times.
Cosmos Dominators will often join up with others if it provides good opportunities for doing evil.
Weapons of Angels
Angels work together in unity, so they usually outnumber the evil spirits, who are always competing with each other. The angels are guided by the Holy Spirit, so they always know exactly what to do. Their main weapon is words. Due to the cross, they have authority on their side. If the people they are working with have submitted to God's will, then together, they have authority over any evil spirits that are attacking. They can speak to them and tell them, "You are not allowed to do that", and they have to obey.
Angels also have the power to restrain spiritually evil spirits. It is hard to imagine what that is like without thinking in physical terms. It seems they can offer spiritual restraint. For example, at the flood, some evil spirits were locked up by the holy angels in a spiritual prison (1 Pet 3:19).
God sometimes gets his angels to deceive evil spirits by pretending to help them. Evil spirits are mostly followers, so they are not very creative or clever. They just keep doing the same things over and over again. The angels have the creativity of the Holy Spirit behind them, so they can come up with creative new ideas that really appeal to the evil spirits. The evil spirits adopt these ideas because they like them, but do not realise that they will actually benefit.
Deceiving angels can easily stir them up to attack nations that are opposing God because destroyer spirits like the idea of attacking and destroying other nations. They think it will give them greater power, but don't realise that the same thing will happen to them, and they will all be defeated.
