So I just started my first encounter with an alien base using V20.
In past past I would go out the little hall to let the aliens know I had arrived then I would run back to the starting room and hunker down as waves of aliens came marching down the hallway and into the room where a flurry of reaction fire would eventually gun them all down. Not this time, they waited for me to come to them!
So finally I make my way down toward the room the occupy, throw some smoke and get into cover to begin my assault. I place a couple guys next to each other behind some cover and what do the aliens do? Toss a grenade and wipe out both guys!
Loving the improved alien behavior!