As we alluded to before, these four cards are from The Lost Caverns of Ixalans accompanying Commander set
They didn't use spears or any kind of polearm, instead relying on more on a firearm called a Dragon
In my first The Dark booster I got Witch Hunter today marked as rare U1 and Ball Lightning another rare U1 and then Maze too in a common
However, its long been thought that the color of the cloud used on the accessory art shows the ink of that card
It just uses the word, "Swamp." Another good example is extort, which has the Black and White symbols in the reminder text, or a fetchland like Mountain Valley that clearly is Red and Green in flavor and mechanically, but is allowed in decks without Red or Green
The Legends Since Homelands is a story-driven set, I figure that the best place to start looking at the cards is with the characters