Today's card is an old tribal dude who's finally starting to get the backup to make him a key component of a highly focused deck strategy (namely discard) and is also a potent in multiplayer games (and is greater-than-linear stackable, an important point for estimations of demand). The rat tribe has gotten some good additions in recent years, from Rat Pack, to Swarm Yard and Cavern of Souls, the seeming interest in discard/hellbent decks with Shrieking Affliction and Waste Not taking this strategy over the tipping point for feasibility, with age-old The Rack. Relatively low print-run, get the foils because it could show up in a sealed product pretty easily.
I see foils at $4.00 by Christmas. Nonfoils will take a year or two to break $2.00, but they're headed there. Another supporting card for the deck will again push demand, and this current (first ever) surge in price is cleaning out a lot of the ambient inventory for this card, so when the next spike comes, it will be sharper.
Notice the "price snapping" to the nice, round $0.50 price point, currently. These are always interesting, and they are most pronounced at sub-dollar price points. More on this later. There's upwards pressure being held back right now, which will cause a sharp rise once the yolk breaks.