Alright, I don't understand what the hell just happened.
I attack with an elven warrior 2/3. He double blocks with Mindless Null (2/2, can't block unless you control a vampire) and Vampire warrior (2/2, at beginning of your upkeep you lose 1 life unless your oppontent has less than 10 life.) I immediately cast overgrowth (target creature gets +3/+3 until end of turn) on my elven warrior making him 5/6.
It then asks me who I want to apply damage to first. I chose Mindless Null, he dies, my elven warrior dies, Vampire Warrior takes no damage. No other artifacts or enchantments or creature effects were in play. Why did my elven warrior die, and why didn't Vampire Warrior die?