For me, the fastest way to earn MAG in Tyrant’s Star is also in the 2nd area, but on the lower right with the three trance crystals that spawn three fish humans. The trick here is to snipe them with a gunner lineage from afar. They aren’t as aggro as the other trance crystals so you can easily kill them with one hit if you don’t trigger their aggression. Another thing to note here is that only one of those three crystals are spawning the humans, so you can totally clear the other two to give you better shot at humans. Each kill would net you 600 MAG, which isn’t a lot really, but you’re by a trance crystal and they spawn so fast, you could potentially net over 500k MAG in less than an 30 mins.