Dimensional Assault Shadow Goblin

The Dimensional Assault Shadow Goblin (ゴブリンアサルトシャドウ) is lower level monster from the 3rd wave. When they are defeated they turn into shadows like ghosts. Because of this, they could not be absorbed until lumped together with the Shadow Lizardman. Together they are responsible for unlocking the Shadow Shield. Found in chapter 『Chapter 51』 of the web novel.