How do the five universal mental factors (sarvatraga-caittas) of the eighth consciousness operate?

The five universal mental factors of the eighth consciousness accompany the operation of the eighth consciousness moment by moment, never departing from it even for an instant, because the eighth consciousness is constantly operating upon all dharmas—it can discern karmic seeds, discern the five-aggregate body, discern the material world (the container world), and discern the mental activities of the manas. Whatever dharma the eighth consciousness manifests, the eighth consciousness can discern it; thus the five universal mental factors will accompany the operation of the eighth consciousness.

As for the mental factor of manaskāra (intentional attention): the eighth consciousness directs its attention to all the dharmas it discerns, turning the mind toward the dharmas to be discerned. Next, it makes contact (sparśa) with the dharmas to be discerned; then it accepts the dharmas it is contacting; afterward, having discerned the accepted dharmas, the appearance of those dharmas arises in the mind. This differs greatly from the dharma-appearance that arises in the minds of the seven consciousnesses: the eighth consciousness does not have the appearance of worldly dharmas, and no concrete appearances of form, sound, smell, taste, touch, or mental objects will appear; but it will certainly discern the distribution and operation of the six great seeds of the dharmas. Afterward, the eighth consciousness's mental factor of volition (cetanā) arises, deciding how to bring forth the corresponding dharmas or alter the corresponding dharmas; by regulating and outputting the six great seeds, it causes the phenomena of arising, ceasing, and change of dharmas to appear. When the eighth consciousness discerns the seventh consciousness, the manas, it mainly discerns the manas's mental factors and the dispersal and concentration of the seeds of consciousness; thereby it knows what dharmas the seventh consciousness is attending to and what it intends to do. When karmic seeds permit, the eighth consciousness will satisfy the desires and intentions of the seventh consciousness.