There are many special achievements in "Little Bones: Hero Killer", and the Ominous Omen achievement is one of them. To do this achievement, you only need to have the Omen Engraving. As the difficulty increases, you will unlock the building, and then you can pass the level. A purple omen chest will appear in the reward chest.
How to achieve the Ominous Omen achievement of Xiaogu Hero Killer
Ominous omen
Possess omen engraving
As the difficulty increases, buildings will be unlocked. Afterwards, a purple omen treasure box will appear in the reward box for passing the level. An equipment with an omen entry will be dropped from it. You can get the achievement by equipping it with the last time, as shown in the picture below.
Increasing the difficulty will unlock the building, and then the level chest will drop the equipment of the Omen entry, which can be used once to unlock the achievement (see below).
