The reason it is called a secret technique, rather than a cultivation technique, is because the use of secret techniques can have side effects and aftereffects, which makes them less desirable compared to cultivation techniques.
Sure enough, hearing that Lu Yu's method to temporarily increase spiritual power by slaughtering monsters was a secret technique, the Core Formation Realm experts lost interest.
"This is easy to handle, I will immediately order people to bring enough monsters here." The City Lord promptly agreed and ordered the generals beside him to have the soldiers gather some monsters into a designated area.
Soon the orders were given, hundreds to thousands of monsters were herded by the soldiers into a specific zone. The City Lord of Beifeng City acted, suppressing a massive amount of spiritual power, directly devastating all the monsters within that area.
