I obtained some cheap pre-painted HeroScape miniatures.  I have rebased them in preparation for using them to use as alien invaders.  Here are a few pictures of them.
Some Marro drudge with their leader sweep the streets for rogue humans

Some Marro drudge with their leader sweep the streets for rogue humans

A pack of Marro hounds on the attack

A pack of Marro hounds on the attack

 

Marro warriors take up firing positions

Marro warriors take up firing positions