Then one usually has to use stronger cultivation resources to have some effect on the body, as Zhang Yi never used any cultivation resources other than the spiritual stones that are only qi in the refined form he could use even the weakest.
Unfortunately, weaker cultivation resources were totally useless to him, so he could start by using cultivation resources for the core creation realm that would greatly help in cultivating his body without impurities.
A higher level feature could be more useful but would also waste a lot of effectiveness and he could not use the lower realms features after that, so he soon decided which recipe to use from what his master left for him.
It was called the 'core reinforcement pill', a pill that could be used to increase one's cultivation speed several times and still help to strengthen qi to improve core formation in the core creation realm and realm of the core revolution.
