[LadyLightning]

Lich with 600 FP spends 300 to erect a barrier. Wins in 2 turns without being hit. Loses 300 FP for 0 benefit.

^ this is a problem.

I would also put in a stipulation that, should a battle end and the Lich still has the Barrier status, he gains
back FP equal to the Barrier's LV. Otherwise, the barrier would need to persist through battles and have an
infinite duration, causing it to last forever or until destroyed by taking enough damage. Also, multiple
castings of Arcane Shield should refresh the LV to the FP spent, and ~not~ stack.