This is going to be a matter of personal opinion, as there is no real way of testing to prove one way or another.
There are many different systems that are all based very similar concepts, including Krav Magna and Jeet Kune Do that are just as effective. Even the Military Hand to hand combat systems are very effective.
Fight Club
a system that's fighting for land
Your question is simple, the answer is complex. The variety of fighting systems means what works in one system may not work in any other system
The immune system
fire truck
That would be the immune system
He was one man fighting against an entire system.
fighting eating and drinking
no its oart of your immune system
A good immune system is the best help in fighting off infectious diseases. If the system is suppressed, the disease has a better chance of getting a foothold.
the purpose was to prevent the countries from fighting they were the agreements
Han Mu Do is a balanced fighting system adapted from traditional and modern Korean fighting arts to counter different combat strategies in the modern era.