Not other than the amount the bidder has available, that is, you cannot stake more AP than you currently have. unless of course you are a PC or major villain, in which case you can always stake up to your beginning AP.
>Because he has a fetch (7W) I presume that he starts off any spirit
>related extended contest with 27 more APs than most of the rest of the
>group. He then unleashes a spirit (often lightning) armed with 40 APs
>and Hero Point. Generally this is enough to result in another 80 APs
>being transferred from the victim, after which he can pretty much do
>whatever he likes. Nothing can stand up to an opponent able to
>repeatedly stake 30APs.
Well, he should not be able to get more APs from winning the exchange than
the opponent has.
So if his opponent has 23 AP to begin with, that is all he gains. No more.
What is always relevant is of course what exactly he is doing when he
stakes those 40 AP.
Such a high bid must mean that he is doing something involving quite a lot of risk to himself. He is after all doing something that might cost him 40 AP.
Remember that he always has to describe what he is doing as he bids, and that there must be a correlation between his bid and the action described. Often problems like this can be resolved by not letting the players state their bids, but instead letting them describe their actions and you, the Narrator, determines how many AP you think the action is worth. The more he puts himself at risk, the more AP it is worth.
And if all else fails, start throwing in opponents with their own hero points to spend to save their lives. If he starts losing 40 AP now and then, he will probably reconsider his tactics.
If he does the same thing in every fight, he is becoming predictable. Punish him for it by allowing his opponents to outguess him, either by giving them a free augment, or him a penalty.
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