“My name is Sardia the Demonslayer. My sword hath slayeth over 2000 demons...or, was it under 2000?”
—Sardia, Disgaea: Hour of Darkness
Sardia appears in the sixth chapter, as one of the demons Laharl defeats to obtain the title of Overlord. She claims that she had killed over (or under) 2000 demons, and that the earth splits asunder when she swings her sword (maybe). Not much is known about Sardia because her appearance was brief, and it is not known what happened to her after Laharl defeated her.
Sardia had her own episode in the Disgaea anime. She had a castle in the middle of a forest, and Laharl and Etna had entered searching for food, since the prinnies wouldn't come when they called. Sardia had apparently been expecting them, since she had dinner ready before they even said they were hungry. She was after the 10 million HL bounty that Etna had placed on Laharl. As they ate, she waited to attack, only to be interrupted by Gordon, Jennifer, and Thursday, who were also after the bounty to repair their ship. They caused a loud explosion that sent Sardia flying, and revealed to Laharl and Etna what she was really up to. She opened up a trap door that sent Laharl and Etna into a large pit, and another that sent Gordon and the others into a tunnel so she wouldn't have to split the bounty with them. The pit Laharl and Etna were in had spears sticking up on the ground, but they slowly floated down and were unharmed. In anger, Laharl cast a fire spell, but a barrier caused it to bounce around inside the pit and start a fire. Water started pouring down, and not only did it put out the fire, but it filled up the entire pit, and Mizuchi the demonslaying shark was released. A window opened up for Sardia to watch the two of them die. Laharl got a hold of Mizuchi and rammed the shark against the window, and Sardia ran off before Laharl shattered it and set them free. Sardia then found Flonne wandering around in the forest, and invited her inside. She assumed that Flonne was only being Laharl's vassal so she could also kill him and get the 10 million HL, but Flonne knew nothing about the bounty and refused to help Sardia because of her greed. Sardia was about to attack, but Laharl and Etna showed up to stop her. Laharl and Sardia then tried to attack each other, but were stopped by Vyers, who insisted that Laharl was his rival alone. They fought anyway, and Laharl pushed Sardia off the balcony. He kicked her sword into the lake and made her become his vassal, demanding to know who told her about the bounty. She then leads him to Maderas's castle. In the end, she is shown washing dishes with the prinny squad.