Powerless Spell

 
Prerequisite(s): None
 
Benefit: You can cast a spell in such a way that it has no effect beyond a simple light show, an obviously powerless version of the real thing with an instantaneous duration and no lasting effect. A Fireball would only be a billowing cloud of hot air, a lightning bolt would become an obviously powerless, but still impressive, display of static. This allows you to show people that you have a powerful spell without expending a high-level spell slot, but the main use is in counterspelling. As it is the spell itself and not the effect that causes counterspelling, such a spell would have very little effect on the real world, but could still be used to counterspell. By giving up the entire spell effect, you make the spell easier to prepare and cast, so that a spell takes up a spell slot two levels lower, but never lower than level zero.
 
Source: Mongoose Ultimate Feats