Semblance Limitations

What is a Semblance?
Semblances are powers exhibited by Hunters and Huntresses in the world of RWBY, much like Aura. Though while Aura seems to posses a stock set of effects for every person, Semblances are unique and individualized. Some, like Blake's, refer to her personality in which she always runs away from things.

Currently, semblance is inferred to by a byproduct of one's aura. Thus, one's semblance cannot be discovered until they have discovered their aura, and discovering one's semblance takes a certain amount of time depending on the individual. Jaune has still officially not discovered his semblance.

Overusing both Aura, and Semblances have led characters shown in canon to experience fatigue. The best example of this is Weiss who collapsed after using a barebones summon.

What a semblance can and cannot do is based on what the semblance is.

What Can a Semblance Be?
Well, that's completely up to you, not wholly, there are rejectable semblances which will be listed in the next section, however, semblances can include, but are not limited to: These are just basic examples, semblances can be more than just this. However, there are basic things which one cannot have as a semblance.
 * Barebone basic elemental manipulation.
 * Perception based semblances.
 * Semblances that act as a stat boost, i.e., speed.
 * Enhanced sense i.e., hearing.

What Can't a Semblance Be?
There are basic things which a semblance cannot be. While the majority of semblances are generally left up to reviewer discretion, there are a basic few things in this list which include, but are not limited to:
 * Summoning: We don't know enough and frankly, is currently a Schnee-only thing so don't trespass on this.
 * Selective Semblances: What do I mean by this? Things like sound waves that affect only certain people who the user chooses. Nu-uh, sound affects everyone and everything, same with light, semblances that deal with light, sound or whatever in a certain range affect everyone even the user, waves cannot pick and choose who and who not to affect.
 * Auto-Hit/Auto-Dodge: Anything which allows a character a basic automatic hit or an automatic dodge, which includes, but is not limited to: becoming intangible, heat-seeking abilities which cannot be thrown off track, etc.

Credits
I'd like to send a thank you to our friends at the RWBY fanon wikia for their distinct rules on semblance. Much thanks to them.