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I think there will need to be more distinction than "this work has cannon weapons".
For example, Kinetic Weapons Are Just Better is when kinetic weapons (such as cannons) in a sci-fi setting are treated as being superior to Energy Weapons, even when energy weapons are available.
For another example, maybe Break Out the Museum Piece if bad guys invade a museum and the heroes have to MacGyver up an American Civil War era cannon to punch a hole in the wall.
In those cases, cannons are being used but there's more context to it.
For cannons in the sense of excessively large weapons, see BFG
When you get to the truly absurd ranges, you get things like Fixed Forward-Facing Weapon (the Logical Extreme form being essentially a gun with a vehicle attached)
For things that aren't kinetic cannons that that can be called cannons sometimes, see Energy Weapon, especially it's subtropes Wave-Motion Gun (example: "main particle cannon"), Magnetic Weapons (ex: "Rail Cannon"), Plasma Cannon (ex:<-), and Ray Gun (ex: "Laser Cannon")
Might also look at More Dakka, the pursuit of which is what makes said fricken huge guns desirable.
Edited by Scorpion451
I for sure thought this would be on here already but I haven’t seen anything. Hand Cannon doesn’t count.