How can I justify not giving my villain the Wish spell?

Question

Basically, I have a wizard as a villain who is ambitious, powerful, and has access to nearly unlimited resources. How can I justify giving him any ninth-level spell but not giving him Wish?

Or, alternately, should I just give him Wish, and if so, how do I keep that under control?

A few details that are specific to my case - He's an illusion wizard, he's one of the primary antagonists but almost certainly won't be the final boss, and he's fairly active in the story, showing up to antagonize the players a la Strahd.

The fact that he isn't designed as a final boss character is a big part of what gives me pause re: giving him Wish, but in terms of flavor I'm really struggling to come up with a reason why he wouldn't have that spell.

Answer 1

He does have Wish, but maybe one of the following either has happened or will happen:

1. He's cast it once, but now he's unable to ever cast it again. From the spell's description:

Finally, there is a 33 percent chance that you are unable to cast wish ever again.

2. The spells fails, anytime he casts it.

The GM has great latitude in ruling what occurs in such an instance; the greater the wish, the greater the likelihood that something goes wrong. This spell might simply fail, the effect you desire might only be partly achieved, or you might suffer some unforeseen consequence as a result of how you worded the wish

Answer 2

The villain might have never discovered a source to learn it from.

Lore-wise, the knowledge how to cast specific spells doesn't come naturally to wizards. They have to learn their spells from ancient tomes and scrolls, other wizards, meticulous study and experimentation or some other source.

Mechanically, this research process is partially abstracted away for PC wizards, because each time they level up they can just pick two new spells they just suddenly know. I know that inferring designer intent is frowned upon in this community, but I would guess this has the purpose to not have every campaign focus on finding new spells for the wizard while still making sure PC wizards get a reasonable arsenal of spells that's appropriate for their character level and fits with the player's vision for their character. It is just assumed that the PC wizard did their studying and research during their off-time throughout the campaign.

But that's not something that necessarily has to apply to NPC wizards as well.

The knowledge to cast an immensely powerful spell like Wish - just like any other 9th level spell - is not something you just stumble upon in a public library. Arcane knowledge of that power-level is usually a well-protected secret held by only a very selected few. Even its very existence might be considered a myth (just because something is in the PHB doesn't mean it's common in-character knowledge in your campaign world). Especially among wizards who specialize in a different school like Illusion, and thus might not be all that well-informed about what is and isn't possible on the cutting edge of Conjuration magic. Yes, I know, that's a worldbuilding detail that's not adequately represented by the spell learning rules for player-characters, which state that learning a spell from a different school is merely twice as hard as learning one from ones chosen arcane tradition. But again, NPCs are not PCs. They do not need to follow the same character building rules.

So it's not implausible that an NPC wizard just never found a source to learn it from, even with "nearly unlimited" resources.

Answer 3

NPCs can use different rules than PCs in 5e

It is true that in 5e, a PC wizard can pick 2 spells each time they gain a level from the overall wizard spell list, so once they get to 9th level, there is no stopping them from picking wish. However, NPCs do not need to follow the same rules as PCs when being built. The DMG says under Designing NPCs (p. 92):

When you give an NPC game statistics, you have three main options: giving the NPC only the few statistics it needs, give the NPC a monster stat block, or give the NPC a class and levels.

So technically, you can design that NPC without elaborating how they got their spells. Why does the Lich not have Wish as its level 9 spell? Why does the Archmage not have Wish as their level 9 spell? Both of them can cast level 9 spells, both of them are official monsters, and the Archmage is without doubt the monster-stat-block version of a high-level NPC wizard. You can easily point to precendent, we don't ask for a justification for those, either.

NPCs are build with story and personality in mind first, and with min-maxing, maybe second. As are many PCs -- not everyone is a min-maxer.

Wish is not the only viable option

A second aspect is that your question implicitly assumes that wish is the best of all the level 9 spells by such a wide margin that there is no competition as to what to pick -- you would always pick it. That both assumes that the wizard is purely about maximizing power, rather than pursuing his interests, and that wish in fact is the best when it comes to power.

And while I agree that Wish is a great spell, and probably the overall best and most versatile level 9 spell for wizards, there are other great spell options on level 9. These options do not run the risk of losing them forever when you use them to achieve an effect you cannot get from a level 8 spell. They are entirely defensible picks, even for a PC wizard. Foresight might beat it for sheer everyday effectiveness. True Polymorph can create all kinds of shenaningans by getting around creature type restrictions of other spells. Meteor Swarm is the king of big area damage.

And if you allow for the wizard having chosen their spells following their interest, for an illusion wizard, Weird (probably the most sucky of all the options) is a pick from their dedicated School of interest.

Answer 4

Here's a few options

1. Consider giving him Wish

Given your comment clarification being concern about the power of Wish, I'd suggest that there are ways to give a character Wish (as would fit with their ambition) without it being overpowered. Given that it's primary function is flexible spell choice once a day, and all other uses risk losing it permanently, it seems reasonable that someone craving power wouldn't want to incur that risk. At a once a day use against an entire party does add an extra punch, it's by no means encounter breaking.

2. Give him something important to have used his Wish on already

Have him burn through his Wish for the day prior to encountering the party. Perhaps something to tie into his villainous backstory.

3. Give him a strong motivation to take a different spell

Perhaps he loves the power to just declare someone dead with a word (Power Word Kill), or has a need to use Gate on a regular basis, or True Polymorph, or Astral Project. Similar to #2, can tie well into a backstory.

4. Don't give him any level 9 spells

He's powerful and ambitious, so perhaps he's still working his way up. You didn't say what level your party is, but if the Wizard needs to be 17 or higher to be a challenge, having Wish probably isn't a big problem for them.

Answer 5

Eliminate Wish from access by mortals -- that is, limit it only to very powerful beings, traditionally djinni, angels, and so forth. Obviously, this must apply to PCs as well as your NPC evil wizard.

If anyone wants to make a Wish, they'll have to find a being that can grant it, and convince them it's a good idea to do so -- likely not so simple, especially for those beings who might be inclined not to seek the least little loophole for an opportunity to thwart the seeker.

This will require altering some magic items, obviously, but that's not a terrible task, compared to keeping a campaign viable when the BBG can just wish away his problems (in the form of the player characters).

Answer 6

Wizards are very egocentric, snooty, and eccentric characters. Maybe he feels that the Wish spell is beneath him and not worth his attention, or maybe he'd prefer to prevail using the spells he's honed and learned over his wizarding career? Plenty of reasons why he wouldn't use the Wish spell that go around the actual mechanics/mechanisms of the spell itself.