Liches are a type of enemy in Homestuck. They appear to be a mid-level enemy. They have bipedal bodies and skeletal heads with large horns. They also wear tattered harlequin outfits and may possess bird heads, wings or tentacles due to prototyping.
In modern fantasy, Liches are typically wizards who have used their powers to gain life after death, which may be the reason for the skeletal heads. Whether these Liches have any powers or not has yet to be seen, as they were quickly dispatched as soon as they were discovered.