Silent Image Question

[magicalmagicman]

1. If you create a wall, is the will save only upon touch? If he succeeds the will save, does the wall disappear or does it disappear only for the disbeliever?
2. What happens if you conjure up a silent great wyrm image and make it act like it's under your control? What saves do the opponent make?

[Curmudgeon]

Saving Throws and Illusions (Disbelief)

Creatures encountering an illusion usually do not receive saving throws to recognize it as illusory until they study it carefully or interact with it in some fashion.

A successful saving throw against an illusion reveals it to be false, but a figment or phantasm remains as a translucent outline.

A failed saving throw indicates that a character fails to notice something is amiss. A character faced with proof that an illusion isn’t real needs no saving throw. If any viewer successfully disbelieves an illusion and communicates this fact to others, each such viewer gains a saving throw with a +4 bonus. So interacting with the wall in any way (touching, attempting to Bull Rush some enemy into it, or whatever) or studying it carefully will grant a saving throw. A successful save only reveals the Illusion to the character who made their save.

The same rules apply. Studying the "Great Wyrm" and noticing that it made no noise would grant a save. The saves are the same as for the wall, only likely to happen sooner. (You don't think there's anything wrong with a wall which makes no noise, so you wouldn't be as likely to study it.)