Shadow Queen

The Shadow Queen is the final boss of Paper Mario: The Thousand-Year Door. She is an ancient, 1,000 year-old demon who once threw the world into the depths of terror. Years ago, four heroes rose up against her, and used the power of the Crystal Stars to seal her behind the The Thousand Year Door. Many years later, Sir Grodus, the leader of the Secret Society of X-Nauts, planned to obtain the Crystal Stars so that they could resurrect her, and use her powers to conquer the world.

Paper Mario: The Thousand-Year Door
After Grodus released the Shadow Queen, he presented her with Peach, which was needed as a vessel for her spirit. After the Shadow Queen possessed Peach, Grodus orders her to destroy Mario and his allies. However, the Shadow Queen refuses, and instead questions the fact that Grodus was giving her orders. Despite the fact that she displayed that she isn't so easily controlled, Grodus still angrily demanded her to do as he says, threatening to "send [her] back into the depths". Insulted by the fact that Grodus tried to make her a slave to his whim, she blasted him with a lightning blast, breaking him into pieces in the process, leaving only his mechanical head. The Shadow Queen then tells him that "[he] would do well to learn [his] place", stating that she takes orders from no one. After the second strike to Grodus' head, Beldam, Marilyn, and Doopliss appear. As it turns out, Beldam was the true mastermind behind the events that took place in the game. She revealed that she was the one who spread the rumor of an ancient treasure that rested behind the Thousand-Year Door, in hopes that someone would find the seven Crystals Stars and break the seal. She had also manipulated Grodus and his organization by telling him a lie, stating that the Shadow Queen would obey the orders of whoever awakened her.

After the Shadow Queen congratulates the Shadow Sirens for their work, she offers Mario and company a chance to join her. They, of course, refuse the offer, and engage her in combat. Mario and his allies won the first round, but when round two began, the Shadow Queen revealed her true form, becoming invincible in the process. She was completely immune to the attacks of Mario and his party. During this time, she offers them another chance to join her, stating that she'll forgive them for their resistance. As soon as they refuse again, the seven Crystal Stars appear, and scatter across the world, returning to the areas that they came from, in order for everyone to send their wishes and positive energy to give Mario and company the power they needed to defeat the Shadow Queen, as well as breaking her invincibility barrier. This also caused Peach to temporarily break free from the Shadow Queen's control, and decided to refill the HP, FP, and SP of Mario and his allies. As soon as the third round began, the Shadow Queen was no longer invulnerable, and their attacks actually began to inflict damage on her. After a long, tough battle, the Shadow Queen was eventually defeated, and Princess Peach was returned to her normal self.

Badges
-Power Plus (both Mario and partner)

-Quick Change

-P Up, D Down (both Mario and partner)

-Power Bounce

Items
- Jelly Ultras

- Life Shrooms

Partners
-Vivian

-Admiral Bobbery

Fighting Styles
-Power Rush style: By buying many Power Rush badges for Mario, one can easily make quick work of the Shadow Queen. Though a risky fighting style, given how little health must be left in order for the strategy to work, with enough Power Rush badges Mario can quickly defeat the Shadow Queen in two or three hits.

Trivia

 * During the battle with the Shadow Queen, the in-battle slot machine is fixed to land on all Shine Sprites, which heals Mario and all of his partners, refills his Flower Points and Star Power, and fills the audience.


 * This is the second instance in which one of the main characters ends up getting possessed by the final boss. This originally happened in Mario & Luigi: Superstar Saga, when Bowser was possessed by Cackletta's ghost.