You project mental energy to form an energy barrier around you that absorbs as much damage as you spend PSI points on it, per turn, for as many turns as you have value in the
Psion trait. +2 in the trait and 6 PSI spent gives you a 6 damage shield for 2 turns.
Should the barrier take more damage than it can absorb during a single turn, it collapses and disappears and has to be re-established by a new usage of the ability.
If the barrier does not take damage beyond its limit, it goes back to full charge on the start of the next turn. If it never takes damage beyond its limit, it lasts the full duration.