Hello today I'm going to break down all of Jewel's abilities.
1. Garnet Gun: Her first technique. She can charge this up as long as she likes and then blast, but doing so gives her a lot of strain on her body
2. Beryl Barrier: This is a barrier that has two modes, Magic and Physical. She can block physical attacks (punches, swords, all that jazz) and magic attacks (Eren's energy bullets, Mercury's Crystals). She can't use both at the same time, so if one's up, she's defenseless on the other attacks. On contact, it will burn the enemy.
3. Danaite Dragon: A huge fire dragon blast that Jewel can use and command. It's not sentient, but she can make it spin around, fly in the air, and all kinds of stuff. She made this on Chinese new year to impress her "friends"
4. Air Hike: She couldn't come up with something clever for this one's name, but she makes a fire platform for a split second in the middle of her jump in order to give the illusion of a double jump
5. Coral Clap: She claps her hands and a heat wave emits from it that blasts everything around her away. Good for getting people off her.
6. Baryte Ball: Ha ha ha! Ronaldinho Soccer! Jokes aside, she basically creates a ball of fire and kicks it at the enemy.