Lets say that this "entity/force/wish" gave you the ability/talent of your choice.
You would be the best of the best in this one field. No exceptions and no challengers could ever compete...you ARE simply that good.
But...the catch is that you could NEVER use it for personal gain. The more you used it for personal gain, the more the ability would melt away.
For Example: I choose "I want to have the ability to play the piano". I thrill thousands of people and donate my concerts to charity, taking just enough money to survive "well". One day I decide to take a a little extra for "my effort" and give a show thats "less than spectacular". I ignore the signs and take more, only to find that my shows "Dont draw as many people". In a final desperate attempt, I charge 50,000 a ticket and give the crappiest show ever.
Once I am penniless and on the street, I volunteer to play for free at a charity auction and the auction makes a tidy profit.
I keep enough to live "comfortably", but realize that if I try to make money, I will degrade my ability.
I have an ability to do ANYTHING I choose, but at the cost of living only "comfortably"...
Question: What would YOU choose as the ability?
Serious answers only...unless you can make them work....

SB
PS. Before you answer, ask me any questions you want in PM. This is actually the basis of a study I did.