I've recently had an experience similar to Tarran's, with my first floater terror mission in my new game. Long story short, after trading four of my rookie team for a batch of floaters and two reapers, I'm left with two Rifle-wielding rookies, and by the sounds of it, about three floaters. All civilians but one are already dead. The pair carefully comes to this house at the map's corner, and find themselves deep in, well, poo - as the three floaters converge on them, killing the last civilian somewhere nearby.
Standing right at the house's entrance, the rookies spot a Floater at ground level. The one closest to it fires a burst! Plink-plink-plink... all shots wasted. Another burst and a snapshot later, the soldier has no TUs left and the alien got two hits, still standing. The rookie further back joins in with his own gun. Snapshot! Miss. Okay, I think, now a burst... First of the three bullets hits! The floater is down. Yeah! Second bullet goes elsewhere, third bullet... hits the first rookie in the back. Aiie! "So-and-so has become unconscious". Well, that's not so bad... Rookie flees into the house. End turn... ominous humming from the second floor... "So-and-so has died from a fatal wound". Ah, damn. Oh well.
With nothing else to do, the rookie jams himself between the wall and the fridge, maintaining a look on the door and the outside through the window. End turn... more humming, a floater enters through the door.. and quickly eats a reaction burst. Okay, one down. Since it's a good vantage point, the rookie remains there and waits. Another floater enters through a broken wall... no reaction fire, but the floater doesn't fire as well. Good! A burst on my own turn kills it, and I'm pondering what to do as consecutive turns yield no progress. Thinking a higher ground will give at least scouting opportunity, the rookie heads upstairs... and stares straight into the back of a floater, who stands facing the window. Hmm. Okay, burst fire.. wait, why two shots? Oh, no more ammo. Wait, no ammo at all? The corpse of the other rookie is too far outside, the still-alive floater will probably have a chance to fire. No laser pistol as backup.. strength too low. Mmkay, there's a stunrod. No chance to use it on this turn though, so retreat into the nook behind the fridge and hope the alien doesn't use fridge logic. End turn... nothing happens. Odd. Stunrod in hand, the rookie walks up the stairs and sees the floater, still standing facing the window. What a weird fellow, got two bullets put through him and didn't even wonder where they came from. But alright, let's hope it's the last one... and stun successful, end mission. Rookie promoted to Sergeant! The final score was in the minus hundred range, for getting five agents and nine civilians killed, but we wouldn't be X-Com if we didn't consider this an acceptable price for 11 dead and 1 live alien... right?