Re: 32 point wizard vs 1st Level D&D Wizard
 

Sure. If you can also keep the dragon from ignoring the snakes and getting at you.

And if you can find a GM who believes that an illusory snake can act like the magical snake created by Staff to Snake[1]. That won't fly at my table. You want an illusion of a snake, then you get a snake. An ordinary snake, maybe with poison (but a ST60 saving throw is pretty reliable).

And, of course, how ought the wizard prevent the dragon from flying? (In my game, a Stop spell did the trick, but that's because the incompetent GM didn't apply the hex multiplier for fatigue. He won't make that mistake again. At least not soon.)

[1] Seriously, is there any reason to think that you can use Illusion to duplicate a Staff to Snake creation with the magical powers thereof? If so, why not duplicate your staff to double the mana available? Set your real staff aside until you drain the duplicate. Hope that someone picks up the duplicate. Kablooie!!

Re: 32 point wizard vs 1st Level D&D Wizard
 

You nailed it with this line above. ITL 139 states, "Magic: Illusions cannot use magic."

So, an illusion of a staff-to-snake would look like a staff... without any magical powers. No occult attack, no snake, no mana, no explosion when picked up, etc.