Guided Essence weapons would need some way of transmitting and receiving information and a way of tracking it's movement. Black magitech weapons could use a bound Hungry Ghost and try to use their risen hunger to try to guide it onto their living enemy before it explodes. They would have to be careful it didn't turn around from it's distant target and move towards living (or dead) targets in their own army.
In Jade Elementals can affect physical objects while remaining dematerialised. Water Jade submarine: the whole vessel is an Essence engine allowing it to move through water. It can dematerialise in water allowing it to travel to any depth.
Dematerialised- something becomes composed solely of Essence. Water has the power to crush, air has the power to float. The deeper in water (or the closer to the water's bottom depending on how you look at it) the greater the power of water gets. The higher up in the air you get the harder it is to float.
Travelling to Yu-Shan means travelling across the infinite distance to the other side of the night sky which is the face of the Celestial Incarnae.
