The transformation mask attained mana through the ...

Association with defeated enemies.

Duration and intensity of the event.

Performers symbolic interpretation.

Viewers understanding of historic events.

The transformation mask attained mana through the duration and intensity of a certain event because to achieve mana you need to overcome certain circunstances in different time lapses. Once you go through this events that represent difficulties and obstacles in order to achieve your objectives, you will attain mana.