Michael

Michael is the first and oldest of the four Archangels created by God, making him the very first angel ever created, as well as one of the oldest and most powerful beings in the universe. During the War In Heaven in the distant past, Michael banished Lucifer from Heaven on God's command, later restricting him to a Cage bound by 66 Seals. He was the Viceroy of Heaven in God's absence and commanded the Heavenly Host before he fell into the Cage with Lucifer. As the highest-ranking Archangel, he issued the commands, which went to the higher-ranking angels to disperse the orders down across the angelic chain.

Personality
Michael is a rather complicated being, having many sides of his personality. He is a strong but strict leader, having set up a rigid and sturdy hierarchy in Heaven, along with strict rules and harsh punishments; likewise, his rule was described as "corrupt," although it wasn't exactly oppressive. Despite this, he kept his brethren in the dark on many important matters, including God's leaving, and punished any who displayed disobedience with death.

To his father God, however, Michael is fanatically loyal and blindly follows God's orders without question, as sees himself as a "good son", and that is what matters most to him. He loves his father dearly and, despite having not seen him in thousands of years, never lost his faith or his love for him. Due to his zealous trust in his father's commands, Michael doesn't believe in free will, not even for himself, believing everything that occurs is how his father planned it.

According to Lucifer, when he puts his mind to something he'll do it no matter how many have to die. This goes along with his intent to let the Apocalypse proceed to fight his brother as his father commanded and bring paradise. He also shares this trait with his counterpart.

He also professes his love for Lucifer, his younger brother, and admits to Tsubaki that he doesn't want to kill Lucifer any more than Tsubaki would want to kill Amara, but accepts he must do it due to his father's orders and the actions of his younger brother. His love for Lucifer is proven true, as seen before the fight where he acts in a polite and genuinely saddened manner, and when Lucifer proposes they "walk off the chessboard," Michael seriously considers it for a moment before ultimately refusing. Despite loving his younger brother, Michael holds great anger for Lucifer, calling him a "monster" and blaming him for all their problems, pointing out they were once "happy together" but Lucifer ruined everything by "betraying them, betraying all of us" and "making [their] father leave."

However, Michael could be wrathful, particularly with anyone who interferes with his destiny, including Lucifer when Lucifer suggests they refuse to fight.

When it comes to humans, Michael seems to be somewhat uncaring; he does not care if or how many he kills. On one notable occasion, he randomly killed a bar full of people just so he could talk to Zachariah. Despite this, Michael also doesn't seem to hold any true hatred for humans, never specifically going out of his way to harm any, or even really bothering about them before the Apocalypse occurred. Unlike Lucifer, he was not angered by God's love for humans being greater than for him, and when asked to bow before them by God, Michael bowed (though this was most likely out of loyalty to his Father). While Michael appears to have an uncaring view of humans, this isn't as extreme as his counterpart, who openly admitted enjoying killing humans.

Michael is in fact in many ways a tragic figure, as both the people he loved the most either betrayed or abandoned him, and all he ever really wanted to do was to prove to his father, God, that he was a good son, the one thing that he never actually managed to achieve.