Tension is a keyword used to describe a temporary form of Exert for channelled abilities or forms of exhaustion. Tension is treated as being the same value of Exert, except it disappeared when the source of the Tension is released.
Tension Cost
The default Tension value for a channelled ability or power is 10. Often, the best way to manage and reduce this value for use is to apply a Metaphor bonus to reduce Tension cost. Tension cost can't be lowered below 1.
Releasing Tension
To 'release Tension' is to dismiss or break concentration on a channelled ability. The user may maintain an ability with Tension even if it surpasses their normal Exert threshold, however the power or ability may be released if it surpasses their Exert limit (the point where a character would fall unconscious).