So in your campaign rolling a natural one on an attack gives you a chance of cutting your own head off?
I guess this is a "yes or no"-question?
The answer is:
No.
So in your campaign rolling a natural one on an attack gives you a chance of cutting your own head off?
Why spend money when the enemy will do the work for you?

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.