Ok so hear me out, previously people complain that Cai Wen last attack is bullshit, but let me explain that it's not.
If Tang San and his small needle could bypass the defence of a spirit sage although holding back, then that just explain that levels between 70 and below has no large difference and still could potentially harm each other.
Here is another scientifically example so you guys understand.
If a human head-sized volume of air suddenly compressed and then exploded, it would likely be a highly dangerous and potentially lethal.
The human head has a volume of approximately 1200 to 1700 cubic centimeters (cc). Assuming the compressed air reaches a high pressure before exploding, the energy released would primarily depend on the pressure and the rate at which the air is released.
To put it into perspective, even a small explosion can have devastating effects. For example, a standard hand grenade contains around 200 to 250 grams of explosive material and has a lethal blast radius of approximately 15 meters (49 feet). The explosion from a head-sized volume of compressed air could potentially have similar or greater destructive power, depending on the pressure and other factors.
It's the same as the previous chapter, Cai Wen compressed his spirit power, using his first spirit ring, and shot it in a single point, it's like a short fueled rocket that immediately ran out of gas if I have to describe it.