Some Armored Skeletons carry around a sword which shoots beams and which is better than a sword made of magical metal obtained from robots, but they never think about using it instead of trying to rush at someone who is using a shotgun that can send them flying.
Santa-NK1s drop a flamethrower even through they only have chain guns, a rocket launcher, and a present launcher; without any signs of a fire-breathing weapon (Probabily they could get that attack).
Some refined bars of metal have a lower value than the equivalent amount of raw ore.
the Destroyer runs away at dawn even through it´s pre-HM equivalent doesn´t do so.
Even through EoS are pretty much made of rotting flesh, only some drop chunks.
The gun-wielding skeletons in the HM dungeon use different weapons than what they drop (Most noticeable with the Tactical Skeleton, which uses a completely different shotgun: They use a shotgun with a rifle grip, an internal clip and without a scope, while the gun it drops has a grip, drum magazine and a scope).
A flintlock pistol can shoot faster than a revolver, or a bolt-action rifle, a shotgun (Both pump-action and automatic)...