Bismuth

"Then you really are better than her..."

- Bismuth's last words to Steven.

Bismuth is a rogue member of the Crystal Gems and the titular main antagonist of the Steven Universe special of the same name. She is a gem that creates weapons and was secretly working on the Breaking Point, a weapon that can shatter other Gems.

Appearance
Bismuth is a bulky periwinkle colored gem with multicolored braids and a star tattoo on her arm. She also wears black and brown suspenders with a bright red star embellishment between her torso. She also wears murky pink pants and dark brown boots. Her bismuth gem is located on her chest.

Personality
At first, Bismuth acted nice and compassionate towards the other Crystal Gems, especially Garnet and Pearl as she remembered assisting them during the Rebellion, but as she was with Steven in the Forge, she showed a more violent and aggressive side to her personality, going as far as attempting to kill Steven when he disagreed on her usage of the Breaking Point on the Homeworld Gems.

History
Bismuth was originally a builder for Homeworld, assigned to help construct the colony on Earth. After encouragement from Rose, however, she fought in the Rebellion alongside the Crystal Gems. She made all of the weapons used by the Crystal Gems during the Rebellion and even took part in the fighting herself.

At some point before the war ended, she created the Breaking Point and presented it to Rose, who disagreed with the weapon and Bismuth's intentions with it. Bismuth, in a rage, attacked Rose under the belief that Rose 'left her no choice' and was poofed by Rose, bubbled, and placed inside of Lion's Dimension.

5,300 years later, Bismuth is accidentaly freed by Steven as he was putting his Thunderbird shirt in Lion's mane. After the Crystal Gems ask Steven to bring Bismuth to them, he accepts. Amethyst and Steven have doubts about Bismuth, but Garnet and Pearl welcome her back with open arms. After Pearl tells her that she has been in Lion's mane for 5,300 years, the rest of the other gems were wiped out during the Rebellion.

Bismuth then brings the Gems to the Forge, were she customizes Garnet, Pearl, and Amethyst's weapons and trains them in order to beat Homeworld. She also has fun with the other gems. As Steven and Bismuth were talking last night, Steven shows Bismuth the sword of his mother Rose Quartz, and she takes Steven back to the Forge were she shows him a secret weapon that would've ended the Rebellion dubbed by Bismuth as the Breaking Point, a weapon capable of shattering Gem shards.

Bismuth then has Steven try out the weapon, which he refuses to do, as that would put the Crystal Gems in the same level as Homeworld. Enraged after assuming Steven is Rose, Bismuth attacks Steven and almost kills him with the Breaking Point. However, Steven manages to stab Bismuth with Rose's sword. After showing her anger on Rose not telling her other Gem cohorts on being poofed, Steven promises to tell the other Gems what happened, enlightning Bismuth before she retreated to her gem. Her gem is then bubbled by Steven and taken to the Burning Room with other gems.

Quotes
"You should have listened to me Rose! I would have taken the war to Homeworld and shattered the Diamonds! I would have liberated...everyone!"

- Bismuth

Trivia

 * Bismuth isn't a gem. In actuality, it is an element.
 * She is the first villain to not be a Homeworld Gem.
 * Bismuth is voiced by Uzo Aduba, an actress known for playing the character Suzanne "Crazy Eyes" Warren in Netflix's original series Orange Is the New Black.
 * Bismuth might have been the same unknown gem that poofed Lapis Lazuli during the war in "Same Old World".