Um, wait, that's not your foci.

[blackstaff67]

Nothing in the rules says you can't...can you use another wizard's focus items?  I have this vision of a renegade warlock stealing someone's foci and using them to create mayhem ("Look out!  He's got the Merlin's Staff!").  I mean, there IS some tradition in fantasy of such things being attuned to only the maker...

By the way, is it legal for a wizard to have two different foci for an element? "This is the blasting rod for Fire that grants me a +3 Power bonus; this is the one for Fire that grants me a +3 Control..." 

[Tedronai]

I'm under the impression that there's a cluase somewhere restricting you to using your own Foci, but my books are unavailable for the moment, so I'm not much help in finding a definitive answer.

As to your second question: that is allowable under the rules.  Some people don't like it, and houserule against it.

[PirateJack]

Ebenezar loans Harry his staff after he turns up at the battle of Chitzen Itza. Mechanically this would be possible because Harry opened up a few focus/enchanted item slots when he lost his staff/blasting rod, but I'd probably houserule it that you have to either be very similar in character to the previous owner (like Morgan's Warden Sword, for example) or the items in question have to be similar to your old ones (like Eb's staff that was made from the same lightning struck oak as Harry's, as well as being made in a similar style).

[Deadmanwalking]

Yeah, that works. But after a bit, like enchanted items, you either need to adopt it (using your own Focus Item slots) or it stops working. So it's a very short-term issue. Also, to get really good use out of it you need to find somebody with the same elemental specialties as you.

And yes, you can have multiple foci for one element, though since the bonuses don't stack (you only use the highest) it really only works with one each for Power and Control.

[Haru]

Your focus items can be pretty much anything you like them to be and have any kind of backstory you like. Including them being stolen from other wizards. Keep in mind though, that a wizard will certainly be able to create a link to a focus crafted by his own hand, so if you left them alive, they might come and look for it. And maybe the magic of the stolen item slightly changes your own magic. Kind of like when Harry ate Kravos. Makes for some great trouble and invocations.

The only thing you have to look at, mechanically, is that you will still have to pay for focus items with your own focus item slots. Of course you can always say the focus you stole has more power than you can get out of, and that is a great way to spend a fate point when casting a spell or justify putting more focus item slots on the item. But reliably, you will only get as much out of it, as your own focus item slots allow.

Edit:
Harry getting Ebenezar's staff in Changes could be interpreted as him getting all kinds of compels early in the book, one of them taking away his staff, and then his player goes and offers the GM a fate point to get his staff back at the beginning of the final fight. Since he is in the middle of nowhere, he can't actually get his own staff back, and after arguing about it for a bit, they decide that Eb's staff should be close enough for it to work for Harry. Also, it gives them a great opportunity to introduce the Blackstaff to the game.

[Vairelome]

Your focus items can be pretty much anything you like them to be and have any kind of backstory you like. Including them being stolen from other wizards. Keep in mind though, that a wizard will certainly be able to create a link to a focus crafted by his own hand, so if you left them alive, they might come and look for it. And maybe the magic of the stolen item slightly changes your own magic. Kind of like when Harry ate Kravos. Makes for some great trouble and invocations.

The only thing you have to look at, mechanically, is that you will still have to pay for focus items with your own focus item slots. Of course you can always say the focus you stole has more power than you can get out of, and that is a great way to spend a fate point when casting a spell or justify putting more focus item slots on the item. But reliably, you will only get as much out of it, as your own focus item slots allow.

Edit:
Harry getting Ebenezar's staff in Changes could be interpreted as him getting all kinds of compels early in the book, one of them taking away his staff, and then his player goes and offers the GM a fate point to get his staff back at the beginning of the final fight. Since he is in the middle of nowhere, he can't actually get his own staff back, and after arguing about it for a bit, they decide that Eb's staff should be close enough for it to work for Harry. Also, it gives them a great opportunity to introduce the Blackstaff to the game.

Perhaps a stolen focus item would come with an Aspect attached, like "[Original Owner]'s Staff"?  This could be subject to the compels you mention above (powerful thaumaturgical link, if O.O. is still alive; reputation issues if O.O. was bad news; other plot hooks as appropriate), and it might be tagged for magical actions that use one of the bonuses on the item.  Alternatively, if the stolen focus item is particularly significant, the player might change one of his own Aspects (normal or Trouble) to "[O.O.] wants his staff back!" or something similar, for the same sorts of compels/tags.

[blackstaff67]

Perhaps a stolen focus item would come with an Aspect attached, like "[Original Owner]'s Staff"?  This could be subject to the compels you mention above (powerful thaumaturgical link, if O.O. is still alive; reputation issues if O.O. was bad news; other plot hooks as appropriate), and it might be tagged for magical actions that use one of the bonuses on the item. 

Well said.  That's coming from a guy that has "I have Victor Sells' Grimoire" as an Aspect.

[nick012000]

Well said.  That's coming from a guy that has "I have Victor Sells' Grimoire" as an Aspect.

Oh, boy. How long is it going to be until he winds up with an Aspect of "I'm infected by Nemesis", instead?

[Mr. Death]

Ebenezar loans Harry his staff after he turns up at the battle of Chitzen Itza. Mechanically this would be possible because Harry opened up a few focus/enchanted item slots when he lost his staff/blasting rod, but I'd probably houserule it that you have to either be very similar in character to the previous owner (like Morgan's Warden Sword, for example) or the items in question have to be similar to your old ones (like Eb's staff that was made from the same lightning struck oak as Harry's, as well as being made in a similar style).

Yeah, as I recall, Harry's monologue says that he can almost use Ebenezer's staff as well as his own for those reasons--so even then, he's getting a reduction in effectiveness, and it only works at all because of their connection.