One hundred percent of orochimaru's men were implanted with mantras, and the mantras that can be perfectly controlled can really bring great power to people, but in the end, the power of mantras was abandoned.
Orochimaru's spell gave people a very strange feeling from the beginning. Generally speaking, only orochimaru can give him the power of mantras, and the power of mantras is also divided into two sections. The first spell is just a lot of black patterns on the body, while the second spell is that the whole person's shape will change.
There are actually no side effects. As long as you don't betray orochimaru, you will always get this powerful force.
The only reason why orochimaru stayed in the spell should be that his own strength and a part of his soul were in the spell. Once chakra, who is implanted with mantras, runs out, orochimaru's power will occupy his body one by one, so as long as there are people who are implanted with mantras by orochimaru, orochimaru is almost immortal.
And orochimaru's powerful mantra seems to be limited. For example, there is only one heaven spell and one earth spell, and it is relatively difficult to extract the spell, so even orochimaru's men are only qualified to obtain the power of the spell. So why did such a powerful spell disappear in the later stage?
The first is the success rate of ninja after implanting mantras, so orochimaru doesn't care about the lives of ordinary ninjas, but every mantras costs orochimaru's strength and a small part of his soul, so orochimaru must be very cautious.
There are not many spell ninjas in orochimaru, and most of them are not as powerful as the second spell. The second spell is very powerful, but the self-attack is also very serious, and the survival rate is very low. I can say that I have completely mastered it. In the plot, there are only four people, including Yinren and Kimimaro Sasuke.
The second question is mainly about the plot setting. The essence of the spell is actually very simple, which is a simplified version of magic. In the forbearance world, besides the magic inheritance of the three holy places, Jyuugo, the ninja of their clan, also has magic inheritance.
Orochimaru's magic essence is a weakened version of magic. Compared with the power that real magic can bring, magic can provide less than half the power. In the later period, even Naruto who mastered perfect magic rarely used magic skills, let alone orochimaru's weakening spells.
The last reason is that orochimaru's research changed its direction in the later period. Mantras can only bring about the promotion of pure strength, and what orochimaru really wants is the promotion of the soul essence.
In The Biography of Boren, orochimaru's child Mitsuki, cloned by his own genes, mastered the power of magic at an early age, so the spell had little effect on orochimaru, so orochimaru naturally gave up the study of the spell, and even the inventor didn't pay attention to it, and others naturally didn't care.