The aliens are just so smart and pitiless! The game does a great job of making you feel weak and vulnerable -- one sonic pulser can wipe out half your squad if you get bottled up. And just when you think you're getting the upper hand, lobstermen show up and cut you to bits, or you discover that your star aquanaut is susceptible to mind control. Guess it's time for another play-through and inevitable defeat :)
Which is unfortunate because they have a strong melee attack and if you can walk up to them, they can walk up to you. You have to either sneak up on them or rely on them being too aggressive for their own good and overextending themselves. The thermal shock bomb stuns them pretty effectively, if you manage to develop it before they show up.
