SLADE3 is a modern editor for Doom-engine based games and source ports. It has the ability to view, modify, and write many different game-specific formats, and even convert between some of them, or from/to other generic formats such as PNG.

SLADE3 can be considered a successor to both SLumpEd and SLADE - it combines the features of both, to create an all-in-one editor. Why does it keep the name of what was previously just a map editor? Because it fits :)

As with SLumpEd and previous versions of SLADE, SLADE3 is fully cross-platform. It can be run on various operating systems, including Windows, Linux and Mac OS/X. So no matter your preferred OS, SLADE3 is available for you.