This question was sparked by a couple of other questions/answers around the effect of Enlarge on an artificer's cannon and an arrow where the wording of "weapon" in the enlarge spell is heavily relied upon:
Enlarge. The target's size doubles in all dimensions, and its weight is multiplied by eight. This growth increases its size by one category– from Medium to Large, for example. If there isn't enough room for the target to double its size, the creature or object attains the maximum possible size in the space available. Until the spell ends, the target also has advantage on Strength checks and Strength saving throws. The target's weapons also grow to match its new size. While these weapons are enlarged, the target's attacks with them deal 1d4 extra damage.
In the artificer's cannon question, a line is drawn between an object and a weapon (though the cannon deals damage it's categorisation is that of a "magical object"). Which lead me to wonder how improvised weapons would be dealt with.
Say you're holding a cooking pot when you're enlarged – something which is normally categorised as an object – would it get enlarged as you are? (The wording does specifically only mention the target's weapons, not other objects, but if I'm right in assuming they don't outgrow their armour the scope must spread to other objects).
If so, would any damage dealt by swinging the pot as an improvised weapon be increased by 1d4 too?
Best Answer
Improvised weapons gain the additional 1d4 damage for a melee attack, but not for a ranged attack.
First of all, the spell's description states that everything (objects, clothes, weapons...) carried by a creature targeted by Enlarge/Reduce is affected by the spell:
In your example, the cooking pot is enlarged as the creature holding it, and it shall return to its normal size once dropped.
A cooking pot is indeed an improvised weapon (it is very similar to the examples given in the rules), and improvised weapons are indeed Weapons: it qualifies hence for the additional 1d4 damage.
The problem is when an enlarged object is used for a ranged attack: as the spell's description says, once an enlarged item is dropped it returns to its normal size:
When it is thrown for a ranged attack a strict reading of the rule tells that the pot shrinks and it deals the usual 1d4 damage.
Nonetheless, a DM may rule that since it is considered as a(n improvised) weapon and not as an object, it does not return to its normal size and it deals the additional 1d4 damage even in this case.