Ok so I found something: I was clearing out a Cesean Base (It was an outpost at the time) and I made it to the Command Center, where a Delta Viper was awaiting me. I had destroyed the door (It was one of those sealed ones that are in transporter rooms) and took a few shots and chucked a few 'nades at it, then I end my turn and it did the weird Shape-Shifting thing (Which i'm sure is to confuse my soldiers as it shape shifts into a Non-Combatant Cesean) and it chucked, I don't know what it was, a Nuclear Warhead most likely. It destroyed the room and my half of my Coyote-armored, Laser-toting soldiers. (the other half were in another room, attempting a flank attack and to wipe the rest of the base) WHAT WAS THAT WEAPON IT THREW AT ME??? IT created a Giant explosion and demolished a transporter room and a good chunk of the nearby hallways, as well as my laser-armed elites. It looked like a C4, but was WAY bigger of an explosion (about 1.5x the size of the standard C4 radius) and... well... I reloaded the save and took out the reactor. Did it somehow get a Plasma Charge (Do aliens even have those?) Any explanation would help, as i'm currently stumped on how to proceed against these in the future.