Sugilite

"Sugilite" is the Gem fusion of Garnet and Amethyst, who makes her debut in "Coach Steven."

Appearance
Sugilite is humongous; at least two times as tall as the fusion Gem Opal. Her skin color is a slightly darker purple than Amethyst's, and she wears a ripped, dark purple, black and burgundy costume similar to Garnet's body suit. She possesses four arms, like Opal. Sugilite wears a visor covering her lower four eyes; her fifth eye is located above her brow. Each of her eyes is a different color. She has a giant plume of spiky, dark violet hair. Her gems are located on her chest and on the palms of her lower hands.

Personality
Sugilite emulates Garnet's headstrong, unwavering nature with Amethyst's recklessness and immense free will. Immediately after being fused, Sugilite considers herself not a fusion of two individuals, but as a single, complete being. The mere suggestion of separation infuriates her.

Sugilite cares for herself, first and foremost. Though she carries out mission objectives, she does not do anything that she does not want to and does not hesitate to use force achieve personal desires. This causes at least one dangerous situation, wherein Sugilite, enraged that she was left behind during a mission and asked to separate, nearly kills Pearl by hitting her multiple times. Despite Sugilite's destructive nature, she seems to retain an attachment for Steven. She avoids targeting him during her rampages and wants to impress him with her power.

Abilities
An absolute juggernaut in combat, Sugilite uses her sheer strength and size to overpower and crush any opposition. Her weapon is an enormous flail that uses Amethyst's whip for a rope, and Garnet's fused gauntlets as a bludgeon. Using this weapon Sugilite easily smashes through buildings, reducing a defunct Gem communications station to rubble.

Though not as acrobatic as Opal Sugilite is surprisingly nimble; she leaps dozens (if not hundreds) of feet in the air and has a running speed close to Pearl's. Sugilite has no known weaknesses. She is only defeated when she is hit on the head by her own flail, knocking her out and ending the fusion.

Trivia

 * In gemstone mythos sugilite stones are known to increase balance of the mind and soul and serves as protection from anger and negative feelings; which is ironic given Sugilite's dangerous and unstable nature (in other words the opposite).
 * She has Amethyst's negative attitude towards Pearl and desire to do whatever she pleases, and Garnet's body shape and glasses.
 * She is the only Gem who's name isn't also that of a birthstone.
 * Sugilite's shades bear slight resemblance to Roy Koopa's from the Super Mario Bros. Series.
 * Sugilite could also be based on an Oni, a Japanese demon or ogre, due to the gem being first discovered in Japan by Professor Ken-ichi Sugi.
 * She also strongly resembles the Hindu goddess Kali. Kali is often portrayed with four arms and a very destructive nature. Sugilite's long and somewhat wild-looking dark hair also resembles common portrayals of Kali. While Kali is often described as violent, she's still usually seen as a destroyer of evil. Some legends even show her with a caring, maternal side.
 * Sugilite demonstrates in the episode "Coach Steven" that if multiple Gems are fused for too long, they can slowly lose their individuality.
 * Sugilite also seems to have sugilite gemstones as fingernails faceted in different shapes. The index is shaped as a star while the rest appear to be square.
 * Sugilite is the largest character in the show so far, about two times taller than Opal and slightly taller than Alexandrite.
 * Sugilite is the only known Crystal Gem with three gemstones.
 * She is defeated by her own weapon thanks to Pearl's strategic planning.
 * She is the only fusion Gem who's full transformation was seen on screen while Opal's transformation was interrupted and not seen, this also goes for Alexandrite.
 * Sugilite, Amethyst, Lapis Lazuli, Alexandrite, and Peridot have not been seen bubbling away gemstones.
 * Since Sugilite has a third eye, it is possible she shares Garnet's precognition ability.
 * She's played by rapper Nikki Minaj