I find it improbable for a living being to be able to reach the thermosphere, let alone breathe in it. Also, I recall that a 2 mile wide meteor could wipe out the entire dinosaurs... or was that 2 miles per a hour? But a 50 mile meteor won't do sh*t to a million ft tall dinosaur.
How to easily win most levels: have good units like swordmen in front followed by endless spearmen. Fully upgrade spearmen, and you will almost always eventuallly overwhelm the enemy.
Guard: Are you sure you want me to leave crates of ammunition on every floor?
Dr. Cordula: Yeah, and leave a crate of mines to. Also, disable the elevator firewall and plant a zombie virus on all floors. While your at it, give a test subject a machine gun and combat rifle. Throw in secret documents about what we're doing in this lab for good measure. Oooh, and program those new shipment of robots we ordered last week. There is no way some one is going to survive with zombies, mutants, killer robots, and no food. I mean, it's not like, this is a game. He doesn't have 3 lives.
Guard: Do you want this to be put into a note/secret document so that some may find it?
Dr. Cordula: Sure, I mean, what are the chances...
This is a great game indeed :) I hope once I'll release an interesting Strategy, too