Sokushi, instant terror

Sokushi is a punch/ability that, for an arm that will be permanently covered with void, time, hell, soul, and reality scars, burns, and curses, allows you to deliver a blow/use an absolute ability that can decimate and turn the tide of battle.
The other conditions to use, rule, monopolize, or even comprehend this attack/ability are that you MUST be a mortal and cannot be using magic (e.g., human, crab, dwarf, elf, etc.). If the being/non-being is an outer existence, robot, god, magical being, etc., they cannot use this. Mortal flesh and muscles must be used, as they are the only things capable of executing this move. Trying to perform this move without being mortal or without mortal flesh and muscles will result in your power, soul, and presence reversing and fluctuating throughout, destroying your powers and damaging your abilities. Another condition is that the mortal flesh and muscles must be trained in combat for 10,000 years or be as strong as really tough steel, as the amount of struggle the muscles and flesh must endure is unbearable for anyone without these conditions.
After fulfilling all conditions, the attack/ability is worth it. If Sokushi is used as an attack, it will break all normal expectations, facts, rules, laws, conditions, domains, effects, barriers, meta abnormalities, anti-abnormalities, skill abilities, tampering, etc. Trying to rule/claim domination of this attack as yours will activate the passive effect of Sokushi; the wielder is completely unaffected by the rulings/effects/abilities of other beings/objects (e.g., domination, fear, barriers, glitches, facts, etc.). The punch can easily one-shot God himself if it hits him; the problem with trying to dodge it is that it counts as a barrier of some sort, which prevents damage and will hurt them instead.
The current wielders are Crushtacean and Crabors.