Element. That was the short name Ying Yue gave to the sword as it summarizes what the sword is about.
All she needs to do was imagine the element that she wanted to summon and within a second it appears on the sword.
The pros are that it can change the sword's elements from fire, air (wind), water, earth, wood, and finally metal. And in exchange, the sword needed some Qi from Ying Yue. Thankfully, Ying Yue's Qi was enormous as she had trained from a young age thus can make a few large-scale attacks.
Yin found out metal could produce electricity and could manipulate magnets as it can attract metal around her easily.
Of course, the wood and earth may seem to be useless to some but because Ying Yue was quite creative from her previous life, she made the two elements unique.
She practised alone at night in the woods far from the campsite until she perfected each move.
With the fire element, she created explosive bursts as well as a hell of flames. An Explosive burst is where the sword would burst out flames like a dynamite bomb. While Hell of flames is when the fire becomes dark purple flames, which was a mixture of both red and blue flames. Hell flames in short and the fire is quite dangerous as the flames will not die out until the target is lifeless or when Yin wants the fire to stop and when it reaches contact with water. (Naruto reference)
While the element of air is also a powerful weapon as she created the Cyclone Twist and Wind assault. Cyclone twist as the name states creates a cyclone of wind that changes size according to the force Yin would apply. Such as, a powerful swing would create a cyclone as huge as a tornado but Yin can cancel the cyclone out by slicing the cyclone with another air slice. Wind assault on the other hand is when the sword is coated with the wind that could make the sword bigger and longer despite its small appearance.
The element of Water proves to be quite helpful as it can produce water but at the same time water combined with air help make ice which created Ice storm (storm of ice) or hail as its stronger version. And Water dance (sword coated with running water making it like a chainsaw of some sort).
Metal. Metal was quite a unique element, to begin with, because the sword can change its attribute to any metal that was like silver, iron and etc. But it also helps become a Magnetic wave (where it can attract and repel other metals). And produce Electric shock (Produce electricity to whatever the sword touches and shocks the target, level of shock would defer according to the force Yin applies.
Wood is interesting because only when the sword connects to the earth can it help produce plants to grow out from the ground or it can accelerate the plant that the sword makes contact with as Yin wishes to however it comes with a cost of her blood being the fertilizer.
Overall, Ying Yue was quite pleased with finding the element sword. However, if this sword existed then there is a chance for other elemental swords to be out there as she realizes there were no light or dark elements that she could use.
Yin would probably only use the sword when it comes to war but for the time being, she would better use the sword her father bought her as using the elemental sword would just invite trouble along the way as she hasn't heard of an elemental sword from the beginning of her life.
On the other hand, Ting Ting was now close friends with Yin and even her brother Ting Yi was jealous of Yin to the point where he threatens him not to be alone with Ting Ting.
Because of this, Yin would often threaten Zao to hang out with the two as Zao is only scary due to his looks. But his real personality was that of a gentle and humble soul who only wants to fight for his country. A real soldier as one would say.
From then onwards the three became close friends until news of a war with the Nation of Qi was heard.
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These are just some of the moves that MC can make. But she is not limited to these moves only and might have more as the chapter goes on :)