The Eldritch Knight Fighter archetype has the ability Weapon Bond where they bond with a weapon, making it summonable and you cannot be disarmed of it. My question is, can you make a bond with an improvised weapon, such as a chair leg or a lamp?
This is one of those situations that the rules don't really cover and as such would be left up to the decision of the DM.
Personally, I'd allow it for the sheer amusement of the player(s) but it would very much depend on what exactly is being used as the improvised weapon.
From the Improvised Weapons section on page 147 of the PHB:
In many cases, an improvised weapon is similar to an actual weapon and can be treated as such. For example, a table leg is akin to a club.
By this statement a DM could definitely treat objects similar to actual weapons as weapons for the purpose of a weapon bond.
However, the Improvised Weapons section also says:
An improvised weapon includes any object you can wield in one or two hands, such as broken glass, a table leg, a frying pan, a wagon wheel, or a dead goblin.
By this statement the players could find a lot of things that wouldn't fall within the "similar to actual weapons" clause and allowing "any object you can wield with one or two hands" to be subject to the rules of the weapon bond could create some pretty hairy situations.
As such I would allow improvised weapons to be bonded but would restrict it to objects that are similar to actual weapons and "common place" objects.
Also, this isn't defined within the rules but I see improvised weapons as just that, improvised, makeshift, and temporary. They are objects that wouldn't normally be classified as weapons except for under certain circumstances. As such it would be reasonable to say that Weapon Bond wouldn't work with improvised weapons because they aren't normally classified as weapons.
My reading is that the EK can, but there is little point.
First, improvised weapons are, well, improvised. You pick up whatever is around and smack someone with it. If you have a class power that lets you summon any weapon, why would you not use it for a real weapon?
Second, improvised weapons are fragile. A lamp can be used as a club, but probably only for one hit. A chair is going to disintegrate after a few hits. A table leg might be good for a couple of combats. Why would a fighter spend an hour bonding to a weapon that's going to break in the first fight?
That said, a fighter who has weapon-bonded their grandmother's favourite frying pan is an interesting idea, and interesting ideas should generally be rewarded.
I would say yes if it made sense. A frying pan or even a rock could be like a club. If the DM doesn't like it, they can come up with a creative way to make it not work before or during the bonding process. Perhaps a wooden chair leg splinters apart or the dead goblin gets smashed to a pulp.