"Anyway it will violate original game play "
I was not thinking about having them do it every mission i was just thinking of a new mission type.
Mission story
Several snakemen get stranded on earth and need to survive long enough to gather parts needed to build a transmitter . As such they lay there eggs in clusters to build there numbers until they can contact mother ship for evacuation .
1:Have several egg clusters on the map
2:Have them spawn a new unarmed snakeman randomly until found and destroyed
3: Have several scavenged weapons around ( human weapons) for there spawn
4: Your Radar has detected mother ship is on approach you have Random number of turns to eliminate as many spawn as possible before it arrives ( bonus points for destroying egg sacks)
5: If you fail what ever number on snakemen still alive at end of time OR before evacuate site get added to the next terror mission
At the very lest this would add more types of games for a " INSTANT BATTLE " option outside of the main campaign