Anyone who read Darth Maul: Shadow Conspiracy (or just read the entire plot of the book on Wookieepedia like I did) will know what happens in the next episode titled "The Lawless". At the beginning of the episode, Satine is rescued from her prison by her nephew Korkie (seen in the Season 3 episode "The Academy"). They escape with the help of Bo-Katan and the Night Owls (the Night Owls are basically the Death Watch ladies who all wear distinctive armor similar to Bo-Katan). Before they are recaptured Satine manages to send a distress signal to the Jedi Council to send help. Darth Maul then reveals that he is glad that Satine contacted the Jedi because he wants Obi-Wan to come.
Obi-Wan goes to Mandalore in the Twilight and though he manages to rescue Satine from prison and gets her onto the Twilight, the ship is hit with a rocket and crashes into the docks. When Obi-Wan wakes up he finds that he has been taken prisoner inside the royal palace just so that Darth Maul can kill Satine in front of him. Obi-Wan is very sad and he's taken back to his cell. The Night Owls save him, though, and they are chased across the city until they find an even bigger battle happening in the docks. I don't know exactly who the battle is between. Possibly the Black Sun and Pykes are fighting the Death Watch, or maybe Death Watch is just having some kind of civil war because Pre Vizla was killed and Maul took his place.
Meanwhile, Darth Sidious arrives on Mandalore and heads to the palace. Darth Maul rushes to him and bows, but Sidious instead attacks them with dual lightsabers. He kills both Maul and Savage.
Bo-Katan finds a ship for Obi-Wan and tells him to go to Coruscant and tell everyone what has happened. I'm not sure what the eventual outcome will be, but it is certain that Mandalore will never be the same again.