Greed 3: Old Enemies Returning
This is the true sequel to Greed: The Mad Scientist (the second in the series, Greed 2: Forbidden Experiments, is an unrelated aberration).
It features slightly improved gameplay as the first Greed, for example you can further examine some objects. Otherwise it's pretty much the same average graphics quality and simplistic animation. The problem is that it is very, very short. I finished it in less than two hours on the highest difficulty. Also, it just doesn't make a lot of sense: from the very beginning the point-and-click puzzles seem arbitrary.
If you really enjoyed the first Greed, then this would be nice little bonus adventure. I think everyone else could easily skip it.