Xenomorphs!
***(Event notifications in italics, suggestion in normal text)***
System Surveyed - Survey Force Geo 004 has discovered Derelict Alien Freighter on 36 Ophiuchi-A V.
Lets have special Alien ruins, not just outposts or cities. Crashed ships, or even functional ships that generate an empty alien colony with a single alien race ship in a task group in orbit.
Officer Update - Lieutenant John Kane of Captain Michael Dallas' Xenology Team has suffered a serious medical problem that will affect his long term health.
Cue facehugger. Pull the affected officer from the Team, kick off a timer to the chestburster event.
Officer Update - Lieutenant John Kane has been killed in a medical emergency.
Start up another timer and run these two events at completion.
Intelligence Update - Alien Queen has been detected on 36 OPhiuchi-A V
Intelligence Update - Xenomorph colony has been detected on 36 Ophiuchi-A V
Unrest Increasing - Unrest levels are rising on 36 Ophiuchi-A V
Create Xenomorph colony on planet - make them immune to radiation and dust levels. Start reducing the host colony growth rate, start killing off population, inversely add Xenomorph population, create Xenomorph ground units on planet. Xenomorphs never surrender, are immune to radiation and dust, generate population from other colonies on planet, and freely create military ground units at will. What can you do? Send in the Colonial Marines of course.
Combat Report - 8th Colonial Marines has lost 58% readiness rating
Combat Report - 8th Colonial Marines has lost 92% readiness rating
Combat Report - 8th Colonial Marines has been destroyed. Colonel William Gorman has perished along with his unit.
Combat Report - Lieutenant Ellen Ripley has managed to escape in a lifeboat.
Run combat as normal. Make sure Ripley survives by generating a lifepod with no time limit in orbit of planet. Is there a way to target your own lifepods?
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Mark the population from the colony as "infected" and also tag any ship that interacts with the infected colony. Civilian shipping should occasionally ignore planetary bans. Uh oh. Nuke your own civilian shipping or hope they don't land anywhere important? Infected ships should make a beeline for the nearest trade center, either their own or a friendly NPR with trade relations so they can "do Business". Troop Transports without Drop Modules should be marked as infected too. Eventually start generating Xenomorph Ground Units on board and run boarding combat.
There shouldn't be a way to eradicate the Xenomorph colony as long as they have a host colony with positive population. They continue to grow from nothing, spawning Ground Units until they finally generate one with Alien Queen, either as a Ground Unit or as a Xenomorph Officer. Better hope that she dies with her troops. Once the host population goes to zero, stop generating Xenomorph pop or GU.
How to end this horrible scourge in your game? Click the Abandon Colony Button. Hopefully no ships in orbit get marked as "infected".
And of course you still have:
Factory Restored - 4th Engineering Brigade has recovered 12 x Xenomorph Infection from Derelict Alien Freighter on 36 Ophiuchi-A V.
Combat Report - 4th Engineering Brigade has been destroyed. Colonel Mason Wren has perished along with his unit.
Intelligence Update - 4th Xenomorph Battalion has been detected on 36 Ophiuchi-A V
Only way to resolve the crisis is to Nuke the entire site from orbit. It's the only way to be sure.