Sorry for the ominous black box in the corner. I planned on releasing this with another, actual artwork, but I’m not sure when I’m getting around to that, so I’ll post this for now. Thanks again to … for the original design.
Pretty much going left to right, sort of diagonally up:
The Longneck Throatslitter is a type of Swordhead with a razor sharp, biological blade attached to its head. It is often used in battle directly by Gravitals, via mind control devices. an experienced pilot can almost always zero in on a neck.
Lancehead. An interesting type with a head crest that is designed to break off into a weapon used by another fighter. Often, this leaves the Lancehead alive, simply so it can be killed with its own weapon.
ShreadBeaks are not at all typical of Swordheads, having a larger beak than snout, and being bipedal. They are bipedal in order to grab enemies, and place them between the hacksaw-like jaws. They often grab either end of an enemy’s body, and use their hands to grind it back and forth on the jaws.
The Flailer (north of last one in the image) is a large Swordhead with the snout heavily changed. It is not technically part of the skull, the Machines having made a mutation to essentially grow a second spine out of the other end of the skull. This gives the Flailer‘s face the mobility of a whip tail, and on the end. its keratinous beak has been fully turned into a spiky ball. It is fed via a hole in its throat.
The Clubber (immediate right) has a fully bony head, ending in a rounded bone plate with knobby protrusions. It has extremely strong neck muscles.
The NightmareFace (top left) is a testament to the cruel creativity of the Gravitals. It has three proboscises, each ending in a beak with spikes pulling backwards, preventing caught prey from escaping. It can kill with these, or retract to proboscis onto its eight, butcher knife-like facial spikes.
Lastly, in the bottom right, is the bullet head. A joke form created to have its head explode and launch the giant beak like a bullet. Not mass produced due to its inefficiency.

great work!
Thanks! These guys are pretty fun to draw :)
rectangle of doom
I was going to past in the person who made the original, but I forgot to before I posted, and now Reddit is being finicky and not letting me edit. It was u/Any_Replacement8244 who made the original.