"Bug Trooper"

[CRGreathouse]

I don't think the bug trooper made it at all into the Monster Manual, like the urd and Dispater. If any aspect made it through, the head does look a bit like a chuul, but not much. There's no way it's a formian, though - they predate 3e by a while, and haven't changed in appearance since then.

Demiurge out.

Yeah, you're probably right. At least I'm pretty sure now I haven't missed something -- I thought there might be something obvious that I overlooked.

Good point on the urd.

 

[Land Outcast]

This exact question was asked before...

I'ts definitely an umber hulk with a slasher graft and Willing Deformity [Gaunt] from BoVD.