NPC based off Gandalf?

[Diamondcat]

I am GMing a campaign with about six PCs. An NPC wizard (not the class "wizard", just a general magic user who has no stat block yet) is traveling with the players on their adventure. His role in the game is to save the PCs every once in a while when they REALLY need it and to have a way to give the players hints in-game. I based him on Gandolf in the sense that he is extremely powerful but holds back, contributing only in small ways when its VERY important (this thread is not about whether Gandolf actually fits that description...I realize there is doubt concerning that subject, just bear with me). He is a member of a council including a very powerful cleric, druid, and sorcerer whose goal is to protect the world from great evils. I need advice on two things: first, I need an in-game reason he doesn't simply blow all enemies to pieces and chooses to make the PCs do everything (my current half-ideas are the council limits themselves for some reason or he can only cast so many spells during his life), and second, I need advice on how often and to what degree he should be allowed to intervene (Maybe a spell cap: so many spells of each level? - or advice on what constitutes REALLY needing help).

As a side note, I am very liberal in my rule usage with this NPC. This wizard doesn't need to prepare his spells or anything. This thread shouldn't be so much about rules, more about role-playing-logical ideas.

Thanks guys!

[Name Violation]

magus with the staff archetype

[ParagonDireRaccoon]

He could be guiding the PCs, helping them reach higher levels so they can fight great evils on their own. Examples of Gandalf-inspired wizards who occasionally do this are Elminster in Forgotten Realms (he did this in one of the Time of Troubles novels if I remember correctly) and Fizban the Fabulous (Paladine in disguise) in the Dragonlance War of the Lance novels. He might also be travelling with the party to make sure they are committed to fighting evil and protecting the weak.

As to when he should intervene, I would plan an occasional APL+3 or even +4 encounter for him to help the party with. If he helps any time they party does poorly, they might lean on the NPC too much and not enjoy encounters ("we just have to stay alive for three rounds and then the NPC will take out the bad guys").

[Cap. Darling]

I would not make him any more powerful then the PCs. There is littel fun in being heroes and doing hero stuff, if you have a DMPC along that can do it all in half the time.
But i they must have him along? My suggestion is that he either conserving his strength for some up coming conflict(between gods?) or somebody just as powerfull is looping for him so he need to keep a low profile. That Way the PCs actually have a purpose and is not just there to make "Dolf" look good.

[Diamondcat]

I wanted to have very little content he was NECESSARY for; he is really just supposed to be a fail safe. The problem is exactly what's been mentioned: I don't want players to rely on him (so by extension I need a mechanic for or philosophy about how often and to what degree he should intervene), and he isn't supposed to do everything for them (which means I need a reason he either can't or won't do everything in half the time and chooses to make the PCs do everything). These are problems I need solutions to (the suggestions so far are helpful; I may use a combination of what's been said and my own ideas).

[Lincoln Hills]

Okay, hm. Been a while since I approached the problem of an NPC who's not interfering (i.e. running the show) but here are some basic notions.

1) The NPC is effectively a 'burnt' agent. This powerful NPC wants to accomplish the task, but is too well-known to his/her enemy. He may be able to arrange a few meetings with the PCs to set the goal and offer advice, but with every servant of the arch-enemy aware of his/her appearance, powers and goals, the NPC prefers to rely on agents who can still operate anonymously. That doesn't mean the NPC will be standing idly around; for more on the uses of a 'burnt' agent, consult Sun Tzu, Macchiavelli, or your friendly local FBI agent.

2) The NPC is morally incapable of certain necessary actions. This is most applicable to outsiders with the Good or Lawful sub-type, paladins, and similar folks. The NPC has foreseen that this mission will require more moral or ethical flexibility than he/she possesses. Although he/she is also unlikely to be willing to openly advocate the use of these methods, leaving things unsaid and hoping the PCs find their own way is generally more permissible. Under certain very rare circumstances, even a Chaotic or Evil character might have objections: for instance, if the mentor PC is evil and knows that the Profane Heart of Cruelty is guarded by nineteen paladins and a celestial dachshund, he is liable to recruit non-evil PCs to do his dirty work (glossing over the details, of course).

3) The NPC's schedule is really, really full. The mentor NPC either has tasks lined up from now til Doomsday or has a single overriding full-time task (such as bodyguard to a young crown prince with 19 poison-loving cousins.) It's reached the point where multiple important things need to be done at once - and the NPC, while powerful, can't be in four places at once; so the PCs will have to do.

[Imbicatus]

4) The NPC has been cursed. The NPS has had a large portion of his power stolen/locked away. Either he needs the PCs help to get it back, or he is incapable of acting at full strength on this plane.

As for mechanics, You can make him a few levels higher than the PCs, but give him Adept caster levels instead of wizard while in his "weakend" state.

[chaoseffect]

An all powerful DMPC with the party is a bad idea. Having someone who has ways to help you but refuses to just fosters ill will: "If you're so f$*~ing awesome then you do it. We'll be over here pursuing our own adventures."

If you really want to go with this idea then I would suggest making him focused only on support spells. Have him occasionally give buffs to make the party feel more awesome and if shit really goes down hill perhaps give him an ability that will severely weaken him temporarily but revitalize the party.

Speaking of Gandalf, have you ever read DM of the Rings? It's pretty awesome and shows what having Gandalf in your party would really be like :p