There were many ways to seal your opponents' cultivation, like subduing them and then put your laws inside their dantians, unless their cultivation is higher than your or someone stronger than you helps them they won't be able to unseal it that easilly; there were also formations that let you seal the cultivation of many at the same time, but that had the disadvantage that not only did it take a long time to complete, but also the formation was easily broken since it had 0 to no defense whatsoever.
These were the 2 most widespread ways of doing that, outside of poison.
There was also one nore way of doing so, but that way was unrealistic, simply because it was impossible of doing that completely, even if you had an incomparably high cultivation.
That involved sealing, or in this case dispersing all the Ki from around your target, that will make it so that your opponent can't recover his spent Ki, but since Ki was present in all beings, be them dead or not, it was simply incredibly difficult to do so.
And besides to make their cultivation sealed, of sorts, they had to first spend all of their Ki, which someone who saw that all ki around them was gone, they would save it to a key moment, so it was simply unrealistic to accomplish that.
Even more so if you were trying to do that to someone who had reached the god realm, they harmonize with Ki itself, they don't even need to try and absorb Ki, the Ki itself comes to them, and besides they can naturally disperse Ki whenever they want, so this was a completely flawed method.
Having experienced a few benefits of the god realm, although she was only half a step in it, Liang Meng could say that at the present there was no viable way to kill gods through this method, much less make them lose themselves inside illusions.
But after a moment she shook her head. She was thinking of killing a tiger without being able to kill a kitten.
First she needed to be able to seal the cultivation of those in front of her at the moment, and the best and most effective way to do so was to slowly disperse Ki, since they were constantly in combat, so they were frequently wasting Ki.
Once one loses the benefits of cultivation after experiencing them, 8 out of 10 would fall into despair, while the rest accept it at first while in the depths of their hearts despair was slowly making its way out, and as time passes they would panic after realising that they couldn't do anything they did before, and they couldn't use their bodies either, since after crippled their bodies got weaker than nornal mortals for a time since Ki was improving them and nourishing them as well, so after the Ki left abruptly it was equivalent to losing all your strength at once, it was terrifying.
So after deciding on the path she would take for now, Liang Meng thought of formations that could accomplish that and began to slowly fuse them intl the "environment" of the formation, unbeknown to the young dragons their cultivation was slowly getting weaker and weaker.
They were fighting for their lives againts gigantic serpents, two headed beasts and even gigantic flying birds, and from time to time other cultivators that were formed by illusions. Some were in ancient ruins exploring them, although they knew this was an illusion they also knew that this was an opportunity that probably wouldn't come again so they decided to take advantage of this.
Liang Meng also decides to try and seal many laws so that even if they had techniques that allowed them to temporarily recover their power or increase it by using many of the laws, it would not happen.
As laws of the world, no matter what world it is, even if it's a dying one, messing with their laws, comprehending them or sealing them is very very difficult. These laws exist to let all beings accomodate within it, to create gravity, and many other things. Basically the laws are what makes a or a world.
So there are many techniques, although rare, that let one become stronger by absorbing them.
Sealing them wasn't an easy matter, but to Liang Meng who had already studied them and comprehended them it was an easy matter, although a time consuming one.
The laws existed all around you, but being able to sense them either required an high cultivation or being extremely sensitive to the changes around oneself, this allowed one to see them and to touch them one had to understand them to be able to either slightly change them in a specific area, or to be able to absorb them, this of course was to those who had an higher cultivation realm.
In that cultivation realm, Liang Meng knew that there were clans that once one of the older generation was about to die they would pass their laws to their descendents, although they wouldn't be able to use all of them, their cultivation would be slightly smoother than most and they had the chance to improve and take those laws a step higher than their ancestors.