I've found the only way to deal with Tyranid's in combat is to stay out of melee.  If you keep it to a ranged fight, Tyranid's tend to get slaughtered, but if they manage to close with you, it's game over.  Fighting in a jungle environment would make that extremely difficult, which does make the Kroot's ability to defeat Tyranid there pretty impressive.  Of course, if Kroot are all like our Arms Master, I can understand why they might be able to do that.<br/><br/>On another note... we're letting Sergeant En set his prisoners on fire and then sacrifice his men in a frontal assault?  One without our help?<br/><br/>Seriously?  We don't even know for certain if the prisoners are Chaos Worshipers, or if they're just innocents being used... and as far as we know, En is just putting on a convincing show to let him get away with his act of corruption, now that he's realizing we might be on to him.