Is this revision of the level 2 Transmutation Wizard feature balanced? [Version 2]

Question

This is a follow up to Is this revision of the level 2 Transmutation Wizard feature balanced?

I will soon be playing a wizard who I intend to become a transmutation wizard. However, I find the transmutation wizard sorely lacking in power (especially because, to me, any level 2 wizard subclass feature has to feel like a viable alternative to Sculpt Spells.) To remedy this, I have begun creating a revision. The first step in this revision is to replace the features granted at level 2 with the following:

Transmutation Savant, which works as normal

Minor Alchemy

Starting at 2nd level when you select this school, you can temporarily alter the physical properties of one nonmagical object or part of it, changing it from one substance into another. When you have an arcane focus or component pouch on hand, you may use your action to perform a special alchemical procedure on one object or part of an object you can see within 30 feet composed entirely of wood, stone (but not a gemstone), iron, copper, or silver, transforming it into a different one of those materials. The object or the targeted part of it must fit within a 2.5-foot cube, and, if the object is being worn or carried, the creature wearing or carrying the object must be willing. This transformation lasts for one hour unless you use your action to end it. The transformation also ends if the transformed material is scrubbed with soap or ash (this scrubbing can be done as an object interaction.) You can use this ability a number of times equal to your Intelligence modifier (minimum 1), and you regain your expended uses when you complete a long rest.

Additionally, you gain proficiency with alchemist’s supplies. If you already have this proficiency, you gain proficiency with one other type of artisan’s tools of your choice.

Much of the minor alchemy feature is copied from here.

My thoughts

To counteract the potential economic abuse pointed out by this answer, I added the ability for others to easily reverse the transformation, and my DM has approved of merchants using this to counter fraud. While transmuting wood to silver can add 10,000 pounds to a block of wood, I imagine setting this up for combat could pose a challenge. An easy way around either of these is my main concern for balance, but I know I could easily be missing something else. Is this alternate feature balanced?

Answer 1

This is still is exploitable

You improved this by getting rid of having multiple features. For the main feature, Minor Alchemy however, in a way this is worse than the first version.

Let's remove the point about using this as a fraudulent source of cash, because your DM agreed to having all merchants in his world now wash silver ingots to check if they are real. The method I think has great flavor, kudos for that. I'd think that real wizards are exceedingly rare in the population, and transmutation ones much rarer still, so this would create a huge societal tax for their existence, if you assume that normal merchants even would know about this. But thats not a balance issue, if your DM is fine to run it that way.

The problem is that the other exploits of the feature are even easier with this, because the activation time is still one action, because it works on range, and because you now can target parts of objects. This still opens up many ways of abuse, here are a few I can immediately think of:

• You can easily transmute an iron lock of a wooden door into brittle wood or porous stone to make it easy to break.
• You can easily turn even a large door into iron in a single use to cover your escape given the volume.
• You can have an ally throw up a piece of balsa wood over your enemies, and ready an action to turn it to silver, to crush them under a 10,000 pound object dropping down on them, every round. Your DM would have to adjudicate this, but a 4d10 like for a collapsing roof trap (a deadly trap for tier 1 play, DMG, p. 121), might be reasonable.
• You can turn parts of massive objects like iron vault doors, or load-bearing columns, or castle walls into soft wood to make it super easy to chop through them and let structures collapse or break and enter blocked areas.

I think all the limitations of long casting time, whole object, and concentration (and while not spelled out, needing to touch or handle during the alchemical procedure) are in the original version for a reason, to block such exploits.

Because the feature as given in the PHB is not relevant for combat like some others, this may make it feel weak in comparison for you, but that is compensated somewhat by its versatility for out-of-combat uses. You probably could address this by just changing the casting time, and leaving the other restrictions in place, which together with a free tool use would seem both fine and less problematic.

Answer 2

Incredible cheese

Starting at 2nd level when you select this school, you can temporarily [...] change it from one substance into another. [...] may use your action to perform a special alchemical procedure on one object or part of an object you can see within 30 feet composed entirely of wood, stone (but not a gemstone), iron, copper, or silver, transforming it into a different one of those materials. The object or the targeted part of it must fit within a 2.5-foot cube, and, if the object is being worn or carried, [...] This transformation lasts for one hour unless you use your action to end it. [...] You can use this ability a number of times equal to your Intelligence modifier (minimum 1), and you regain your expended uses when you complete a long rest.

These are the relevant parts that make this absolute cheese. You don't use it for money, you use it to make doors nonexistent, collapse mines, and cause utter destruction.

A locked door? Turn the lock into soft silver and bend it open, or wood and set it on fire. You just made the fighter's strength and rogues lockpicking and the knock spell obsolete, one level before you even get access to knock.

A mine tunnel propped up with wood? Turn the nail-wedges that lock the supports together into a weaker material and the ceiling comes down - you turned any place like that into a trap hallway.

A trap? Turn its springs into wood and it stops working. You just completely obsoleted another skill from ever being needed - one that usually requires touching the item even, as this works on sight!

You're arrested with manacles around your hands and still in transport? No problem, obsidian (volcanic glass) or flint are very brittle and pretty equivalent to glass from the object table. So you turn your manacles into a fragile glass-equivalent (AC 13, 2 HP) and fall them against a wall a couple of times. No need for a rogue to prepare your "daring escape" or the Barbarian to bend them open. Congratulations for hogging the spotlight and invalidating both strength and dexterity.

Need to block a door so followers can't come in? Carry around a pair of granite wedges, turn them both into soft copper, put one under a door, push the other one under the door from the other side in the same spot, then hammer it in super tightly so that the two copper wedges interlock extremely tightly and mold to one another - and then end the effect. You just turned a door inoperable but for someone literally blowing it out of the frame - each of the stone wedges has about AC 17/5 HP (stone / tiny resilient), which makes them harder to destroy than the door that would be about AC 15/4 HP (wood / medium fragile) according to the object rules. Oh, and as a bonus: you just invalidated Arcane Lock, a 2nd level spell, one level before you get access to that!

It even gets worse once you realize that slate is extremely brittle and an even better choice to turn structural things into - like the keystone of a bridge. Slate is pretty comparable to glass, meaning AC13 and also fragile - which means about 2-3 HP. As a result, you can very easily prepare a whole bridge to come down by turning the keystones into easy targets that can't sustain a single attack. Add to that, that if enemies are on the bridge, they are most likely incapeable of continuing the combat. That is way overpowered for a 2nd level ability.

How to fix it?

And that's just the tip of the iceberg. Clever use of this is an extreme spotlight hog, and lessens the time more mundane characters gain it - their abilities take usually direct contact with the item. In some cases your ability and their skill can work together, but with one action for your ability you just overshadow them.

The PHB made the ability take 10 minutes for a reason: one action transmutation on sight is incredible cheese, and if you are clever, even 10 minutes can be exploited for the effects above - just not as spectacular. The easiest fix to the ability from the PBH is just taking it as written and reducing the required setup time. At least 1 minute should be taken to keep it from becoming overpowered and outshadoing spells and abilities that take an action. One minute also would make it somewhat more versatile without becoming a spotlight-hog.