Rann took three days to cultivate.
The essence crystals planted and crushed, while the mist of essence, absorbed into his core by him. Rann did not relent, he did not give up.
He understood how vast his energy core is, almost twenty times the size of a normal Martial core, definitely it took more time to saturate than the normal one so, Rann was patient.
Finally, his combat ability instantly hit 2000.
Rann would have continued cultivating, but... he did not have much essence crystals on him. Most of the essence his father had given to him have simply been exhausted in a span of three days.
The realization dawned on him that the core of a Vanisher seem to hold way too much essence in it.
Now that the second core had been saturated, it was just the third core remaining before he attempts another breakthrough.