Notes from author
YOU SHALL NOT PASS!! (Especially when I'm using tranquil walk of peace + wrath of the gods)
This is not a sorcerer build named gandalf. This is a full cosplay gandalf build. The magical abilities gandalf showed match more with miracles, and tranquil walk of peace is perfect for the meme.
The catalyst is just for aesthetics and cast light. I choose Tin banishment because of it's size, but tin darkmoon is also fine.
If you want more stats you may use longsword (probably chaos one), instead of silver knight sword, and maybe go all in with 50 faith. I don't care very much for viability when I'm cosplaying.
Also, any starting class is fine, choose the one you are more confortable with.