Well. You see, the Thorian has these things called "Spores" that it uses to control people. They probably work like an interface. Or a USB cable to the individual's brain, which the Thorian uses to control them. In this fic, the Thorian is also a Psi who's been experimented on by Ethereals. It's also damn old, so it's good at what it can do. Simply put, it read their minds, bro. Either Kaiden's brain when it mindfucked him, or learned it from the people already on Feros. It's not hard to imagine one or a few of the Xeno's learning English. edit: Is the Thorian a fruit, or a vegetable?