There aren’t many $2 commons in Magic, but Shadowmoor is a set that has a few valuable commons. Gleeful Sabotage is also a fairly underrated card. The fact that it can easily destroy two targets quite easily for only 2 mana, due to its Conspire effect, makes it pretty efficient. It can be even better with the more creatures you control. Honestly, it’s a bit of a surprise that it doesn’t see much Modern play, but maximizing its usefulness requires you to run a lot of green creatures. Mono-Green Aggro is a real deck in Modern, but not one that has made great waves.
Obviously, there’s enough demand for Gleeful Sabotage, though, that it’s close to selling out just about everywhere. There’s another printing, albeit quite limited, from one of the Archenemy decks. This is a common that could be reprinted in the future, but having the Conspire mechanic limits where exactly it could be printed. Whatever you do, don’t pass these by if you happen about them in some random box of commons. I wouldn’t go out and pay $8 for a playset of these, though. Regular vendors still see this as well under $1. But it’s good to know that this is a card worth watching.