I am DM a game and the characters found a Deck of Many things. One of the characters got 1 wish. She wants to use it to gain a Feat. I know that I will NOT let her gain a benefit on a stat. But what are your opinions.
Thank you.
At our table, any wish that isn't the duplication of a spell of 8th-level or lower (or one of the listed alternative effects) is considered to have an uncertain outcome and thus an Intelligence (Arcana) check is called for. On a failure, the spell goes awry in an interesting way. So increasing an ability score or gaining a feat would fall into that category.
What level is she? How about pitting her vs enough monsters to level her up until the next feat level?
What's the wording of the Wish and which Feat? While the spell takes out some of the "screwup" factors by listing what can be safely wished for without description, anything else is fair game for capricious powers that be to addle the speaker. The game world loses a bit of versimilitude if a player can simply say "I wish for a [Feat]." It's unlikely the world you're in has a Player's Handbook. In older editions, "selfish" wishes or those outside the scope of "known" wishes that don't have side effects were subject to DM fiat. In any case, a Feat is an amazingly powerful modification and you'll need to consider if approving such without side effects will change your game.
What race is she? If she's not one already, change her race to the variant Human, boom, extra feat. If the wish is worded vaguely, this is the kind of thing a greedy player should beware of.
I'd encourage her to describe the wish she is making, without reference to game mechanics. The character wouldn't say, I wish I had the "crossbow" feat, They are more likely to phrase it as "I wish I was the most famous crossbow woman in the land". This opens up far more ways that you can make the wish come "true", maybe she gets a magic crossbow, or finds gauntlets of archery. Maybe she gets a feat now, but not when she goes up the next feat gaining level (an advance on power as it were). Or suddenly everyone in the kingdom knows she is a natorious highwayman and she is hunted for crimes she never did. (But if I did this I would check with the player if she would be happy with this change and give her some compensation such as the feat (so if you want the feat there is a downside with it)).
Why is it that, after all these years, the very first thing people start suggesting is how to screw over the player in question with their wish? Honestly, you put that Deck of Many Things into you game. This was prbably one of the least problematic outcomes that could have occured from that. Live with the consequences of that DMing decision, let the player have their freaking cake, and learn not to include potential wish-granting items in the game if you want to avoid this sort of situation in the future. 
Alighty, deep breath.
If you are REALLY worried about it, why not just have the wish provide the feat temporarily? Let her have the feat for an adventure or two, then have the magic fade. And, most importantly, let her know that this is temporary. Don't be a 
and just yank it away with no warning. Just mention that the magic can provide her the boost, but the boost isn't a permanent part of her character unless she actually spends a stat adjustment on it. Leave all this nonsense about character screwage for "balance" buried in the past where it belongs.
Yes. I opened up a can of worms. But things happen.
Her wish was
"I wish I can use my full dexterity bonus (her dex is 17) when I wear medium armor. "
From some comments, I can make her dex 16 now
What is it with DM’s and screwing people over with wishes?
Compared to creating 25,000 gold coins or giving up to 10 creatures resistance to a damage type forever just give her a feat which lets her use her full dex in medium armor for crying out loud.
Why do you hate this player? You allowed the wish in your game, take some responsibility.
Sorry if I’m sounding harsh but this has been a trigger issue to me for 20 years.
NirvanS wrote:
NirvanS wrote:
I don't think it is much to ask considering other things players can ask for.
And with respect to a DM adding a DoMT to a game. There are adventures that give ridiculous gifts/abilities. For example the Egg of the Pheonix, a dragon bestows each player an array of powerful magic items to choose from. In Sword of Hope, a book grants a single player +1 in Intel, Wis, and Char. Granted, these adventures are 1e, but they are examples of gifting players with stats or powerful weapons
gaining a feat or bonus to a stat is not something that a player can ask for. That is beyond metagaming and flat out cheating. There is no possible way for a character to ask for a feat that does not involve them asking for a game mechanic and referancing a rule and not making any statment as a character. The must ask for a wish as a character not as the player. A character can not know about the six stats and feats that is player only informaiton.
Seriously just make sure you advise them to start playing as the character and this should go away.
Drycanth wrote:
iserith wrote:
Drycanth wrote:
But a wish is a way of cheating.
In 2e. You can wish for an increase in a stat. But once that stat reached 18, you needed 10 wishes to reach 19. Then another 10 wishes to reach 20, etc.
Proof you are Allowed to increase a stat legally by D&D rules.
What else is fair to wish for instead, The power of Elminster, or dragons later sword for Tiamat