During the second year of making golden cores, Lin Yi stopped following the regular alchemy routine. This was because his Dantian was already accustomed to the scorching of the Dan fire, and he no longer felt any pain.
Therefore, after informing the Pill Immortal Master, he began refining two lumps of spiritual liquid simultaneously. Each lump of spiritual liquid was refined under the heat of a wisp of Dan fire, and his focus was more intense than before.
The scorching of the two wisp of Dan fire was a tremendous test for the Dantian. Fortunately, the Dantian remained sturdy and managed to bear it, but it also brought him a greater feeling of pain than before.
Lin Yi believed that refining two lumps of spiritual liquid within the Dantian at the same time should be the limit. If there were any more, he wasn't sure if his spiritual concentration could bear it, and it would likely cause problems with his Dantian.