(As seen in this story)
Sign of Thanh
This Sign is a glowing rune, drawn on any surface or even in the air. It remains in place for as long as its caster concentrates, visible even in darkness and potent to about fifty meters [Edit: “area” range]. All within this range who look upon the Sign must pass a Psychic save or be paralyzed, unable to move voluntary muscles and barely able to breathe, until the Sign is allowed to fade. A caster who looks at his or her own Sign after its creation may also be frozen, and will maintain it involuntarily until his or her strain meter is full and he or she has to make a break roll.
The caster chooses the difficulty, and this becomes the difficulty of the save. The base cost is one strain per round. This length can be extended, increasing the difficulty by two steps for each step in time, or the difficulty can be lowered one step by doubling the cost per round. By taking on additional strain when the Sign is first drawn and each unit thereafter, the caster may add a penalty to others’ saves (on a one-for-one basis).