Would allowing Wizards to use Wisdom for AC be unbalanced?

Question

I find myself frustrated that Wizards have high incentive to invest in Dexterity and Constitution so that the aren't quite so squishy whereas they have little incentive to increase Wisdom except to help their Wisdom saves. Wisdom, however, seems much more in line with the common imaginings of a Wizard than Dexterity.

I am considering house-ruling that wizards can choose to add their Wisdom modifier to their AC instead of Dexterity but I want to check whether that would be balanced. Essentially any time AC is mentioned they could substitute WIS instead. Without mage armor they could have 10 + WIS, with mage armor they could have 13 + WIS. I don't think I would allow a multiclass to use this.
A lore justification for this would be their arcane studies have caused them to subconsciously weave magic around themselves making them more difficult to hit.

A relevant aspect to this change is that wizards have Wisdom Saving throw proficiency so this would allow them to be really good at Wisdom Saving throws more easily. On the other hand Dexterity saving throws are also quite common so giving up points in Dex also has a high cost even without AC.

Answer 1

This is not broken, but it's not super helpful, either.

Normal wizards care mostly about INT, CON, and DEX, and they care about WIS a tiny bit because it's an important saving throw. A wizard might start with a stat array like 8/15/14/15/10/8 (before racial modifiers).

A wizard using your house rule would care mostly about INT, CON, and WIS, and would care about DEX a tiny bit because it's an important saving throw and their initiative score is tied to it.

Arguably this makes the wizard class a little bit worse, because now there are two things they care about that are tied to their fourth-most-important stat, instead of just one.

But it's certainly not broken.

Answer 2

Wizards have low AC if they don't invest any resources in AC. They have similar options for high AC as other classes.

AC 14, from 12 Dex and Mage Armour, is a reasonable AC, with a relatively low investment.

A lore justification for this would be their arcane studies have caused them to subconsciously weave magic around themselves making them more difficult to hit.

That's what the spells Mage Armor and Shield are for.

It's not particularly imbalanced for Wizards, for the reasons that other answers go into, but it will open other people asking for the same. Would you give Wis to AC to Clerics and Druids?

Answer 3

No it would not be imbalanced

For a wizard, intelligence is all that really matters, anything else is a secondary stat used for a specific purpose. Pumping DEX or WIS for AC give very little additional benefit because outside of AC and a few skills they have no interaction with any of the wizards abilities.

There is even a passage in one of the manuals (I can't seem to find where) about being able to re-flavour classes in this kind of manner.

However:

I really don't see the need, and frankly if you are worried about AC on a wizard you are failing to use the toolkit that you are provided. The difference between say 14 AC and 16 AC is very little once you add a few levels, essentially you are still going to be hit by anything that wants to hit you.

Your survival doesn't depend on AC, it depends on you not being somewhere that you will get hit, or locking down the enemy that wants to kill you, or enabling your friends to kill those enemies faster.

I would urge you to look at the way you are playing and the spells you are picking before doing something like this, at least for the reasons you are doing it. If you want a wise wizard then just pick wisdom and be satisfied with the RP element without worrying about the power-gaming aspect. In fact that might help, because a wise wizard would know that not being attacked is far better than a few more points of AC.

Answer 4

TL;DR: Yes what ever way you are doing it, it would be unbalanced in the too strong way or too weak way

1)another way to calculate AC

Let's say that your feature is another way to calculate AC (like most thing that look like that) your wizard AC would be 10 + wisdom. But now it make your wizard have to choose if he prefer 1X+dex when he use an armor (mage armor, light armors, etc...) or 10 + wis. So the feature is useless from level 1 to 20 (most scenarii, mage armor will be stronger).

2) replace AC in all calculation

Now let's say it would be a replacement of dexterity for all ways to calculate AC. Now your wizard AC will be 1X+wis with an armor. But if the wizard take 1 level in monk, it will be overpowered, because now it's AC will be 10+(2*wis). Weither a monk will take 1 level of wizard to have an insane AC without needing any point in dexterity and have spells that can help him in most situation, or a wizard take one level of monk to be more tanky than most melee combatants.

The only way to counter that bad effect is to say "you can't multiclass".

3) give the wizard the monk Unarmored defense feature

One hybrid solution would be to give wizard the monk Unarmored defense feature. But it's invalidate mage armor and give the wizard a strong, evolving defense at no cost. At least magic classes with this kind of feature have to sacrifice something (Sorcerer can have this only if they are draconic, Warlock can have it only with an invocation) and those thing are limitated (at 18 (13+5 dex mod), where monk Unarmored defense is caped at 20 (10+5 dex mod+5 wis mod)). So it still very strong, and I might even be overpowered.

Now why want you a wizard to have a good AC when are, from all D&D edition that I played, the magical glass canon?