Was thinking of a TFTD version of human traitors mod, adding a new alien race to the game with its terror unit.
The alien race are human traitors referred to as Murmillo, wear unique red diving armor distinguished by its finned helmet and is stronger than regular diving suits and almost as strong as the aqua plastics armor. Murmillo have similar stats to XCOM aquanauts and are equipped with sonic based weapons, just like the rest of the alien forces. Their Navigators and Commanders are capable of Molecular Control, and they are quite good at it. They start appearing from the 2nd month onwards and remain one of the more common enemies, even in late game as they are generally the more balanced enemies with the alien life forms. (They do make human screams upon death.)
Murmillo are generally composed of criminals, terrorists, and even people from organizations corrupted by alien infiltration.
The land terror unit that accompanies Murmillo is the Turdent, it has no ranged attack but but the Turdent's shell gives it extreme armor for its small size and it can take even more punishment than the Triscene. Its jaws can potentially tear through even tough armor and will happily chomp at aquanauts and civilians alike.
The sea terror unit is the Shocktank, a Coelcanth variant with melee and ranged electrical discharge attack and a volatile power source. If it is destroyed, it will explode, potentially killing nearby victims.
