Dark Injection is a Spore mod brought to the people of Spore by the mod-king Davopotamus. The mod's primary function is to make all Darkspore editor parts available in the Spore creature editor (which includes many of Spore's outfit parts as well as some forty pages of never-before-usable-in-Spore parts that had previously been thought the exclusive province of the Darksporeons alone.)
The mod has gained incredible popularity, and many creators who had been unwilling to mod their copies of Spore prior to this mod's release jumped at the chance to get Darkspore parts onto their creatures. Rebecca1208, arastoph and xDoomsoulx, among other well-known creators, were quick to post examples of the awesomeness that had been made accessible by the mod-king's handiwork - and there was much rejoicing.
Currently, the only known issue with the mod is that it fails at advanced painting. Consequently, all the good screenshots are taken from the editor mode.
This mod's thread has always been among the first few non-stickied topics on the first page of General Discussion ever since its inception.