Tyranid "Death-Star" horror stories.

I played a 1850 pt seize ground mission with three objectives on the board. Ultramarines Vs. Tyranids (classic) Two rhinos waited in reserves, a sterngaurd and terminator squad waited for the deepstrike and I had a predator, scouts, and devastator squad on the board. First two turns involved shooting, as these units had castled within run-range of an objective, it wasn't until the third turn when things picked up as one rhino came in and the termies deep struck, though all of this is irrelevant. What I'm getting at is that while my tac squads where pounding bolter lead into gaunts and holding objectives, my terminators where dealing with gun guard and a tervigon the "death star" had tore through my back line destroying an entire devastator squad (310 points with 4 LC), my predator (auto las) and a rhino which I had put to block them from reaching my scouts who were contesting an objective. I pulled away with the win thanks to a late game deep strike from my sterguard who contested an objective, though paid a heavy price.