As a DM, I’m not sure I would allow wish spells in my game. At least not the full-powered version of them. I’m not evil enough to twist my player’s wishes, and giving them too much for free just unbalances the game. Plus, it just seems like a writing shortcut – sure, they could work hard at completing a quest for a specific goal, or they can just convince a genie to give them what they want.
I always wonder exactly how much you can game a genie’s wishes so that you maximize the output. For example: For Bob’s three wishes, he asks to be able to fly, to have X-ray vision, and to be invulnerable. But then Fred expends one wish and says, “I wish I had all the powers of Superman.” Or take that even further: If you were an short, 80-year-old woman of Asian descent, could you say “I wish I was Superman” and come out looking like Christopher Reeve? With a single wish, you would change your age, race, sex, and height, and get several super powers to boot. And if you can do that, what’s to stop you from designing a fictional character of your own, and wishing to be them?
Before you say no, remember: When Aladdin wished to be a prince, that was a huge package deal. He got new clothes, an entire parade’s worth of riches, hundreds of servants, his monkey was transformed into a different animal, and the genie even wrote him a catchy song. That’s at least three wishes right there, but he got it all just by wishing to be a prince.
On the other hand, the Disney Genie may have been a fraud – it can be argued that he never actually made Aladdin a prince, he just dressed him up as one. Aladdin constantly worries about being found out. If he’s actually a prince now, that means there’s suddenly an actual king and queen out there somewhere claiming parentage, and Ali has nothing to worry about. It’s not just a costume if Genie properly altered reality to make him an actual prince, like he promised. But there’s no evidence that Genie actually changed his pedigree, he just gave Aladdin a really elaborate disguise.
But let’s assume our hypothetical D&D genie isn’t a fraud. For the sake of argument we’re using Disney’s rules. Sure you can’t wish for more wishes, and the genie can’t grant life, death, or love, but everything else is fair game. More importantly, the genie isn’t demanding an immediate answer, and is living with you as a friend. Disney’s Genie pals around with Aladdin. They have serious discussions. There’s no reason they couldn’t discuss exactly how wishes work, the limits, and the most efficient ways to phrase them. So if you have three wishes and more than three heart’s desires, you should do exactly what Aladdin did: offer to split your wishes with the genie. But make sure the genie’s wish is dependent on your satisfaction with your own wishes.
Tell the genie, “Look, here’s a list of all the things I want. If we can find a way to cram all these things into two wishes, then the third will be used for your freedom.” Then maybe he’ll let you get away with things like, “I wish I was a young, beautiful, wealthy redhead.” Of course, the genie will be skeptical that you’ll actually free him. Not because he doesn’t believe you, but because he knows wishes are addictive. He’s seen this before. You’re sincere now, but after the first two wishes you might change your mind and keep the third for emergencies.
So maybe there’s a way you could set him free with your first wish? I’m no lawyer, but something along the lines of, “For my first wish, I wish that, upon completion of my second and third wishes, if I am satisfied with the outcome of those wishes, the genie will be set free.” If you made such a wish, there’s a good chance the genie would work extra hard to make sure you’re satisfied with your remaining wishes. Again, this is why I’m reluctant to allow wishes in my own campaigns. I don’t want PCs to overthink it this much.
And there’s always that one small worry… Sure, the genie trusts you enough to make a deal. But can you trust the genie? I’ve seen Wishmaster, they’re not all good creatures. What if I set him free, and he destroys the world? Your wish should probably include something about making the genie mortal when he gets his freedom. But then you run the risk of losing the genie’s interest. Some genies would be grateful for the chance to live an unchained mortal life, but others might not want to give up their immortality. They might be less inclined to work with you on crafting the perfect wish, if the result means having to get a real job. Or you might get everything you want, only to be immediately stabbed in the back by a now-mortal genie, who takes your newfound wealth as his own.
