Unshakable Chill

Source unshakable chill

On a failed save, the target immediately takes 1d6 points of nonlethal cold damage per tier. Add your tier to the DC of any other Fortitude saves the target attempts to resist severe cold as part of the spell's effects. The target also takes a –4 penalty on saves against spells or effects with the cold descriptor.

Augmented (5th): If you expend two uses of mythic power, the target gains vulnerability to fire.