My friends no longer allow me to GM these types of games. Mostly because I have a rep as a Killer Game Master. Granted, once people started whining about how suicidal my campaigns were I started to go out of my way to make nearly impossible missions for my players, so I guess the rep is accurate. Course I also play with a few munchkins so I kind of felt obliged to go out of my way to keep them from borking the campaign in their favor.

My favorite scenario was from the Palladium Robotech books in one of the Sentinels campaigns, where it was a small reconnaissance group trying to answer a distress call from some not too happy to see the humans Robotech Masters, who quickly tried to kill the group in order to hijack their ship, except as the fight went on, the Invid showed up and took out the party's reconnaissance fleet in orbit and then damaged their own vessel, stranding them on the planet with a three way conflict with the Invid and Robotech Masters. A truce was almost made until the Zentradi showed up to answer the distress call and the RM back-stabbed the party. Course the Zentradi started a total bombardment of the planet and ignored the RM to fight the Invid and well it kind of turned into a four battle and the party made the unfortunate decision to try and use what protoculture they had to get the RM ship back up and running to escape, but the moment that thing lit up, the Invid swarmed it and the Zentradi fired upon them. I can't remember if the Invid took them out or the friendly fire from the Zentradi blew them both out of the skies. To suffice to say, no one made it off the planet. Good times.