Alien NPC enemys?

[HALAKxTEHxOWNER]

I was thinking one day when playing planetside:
what if the game had hostile-to-everyone cpu aliens? they would mostly be weaker than players but with multiple types, some incredibly strong and rare, some worthlessly weak and incredibly common.
it would be like every day a randomly chosen continent would be attacked and have aliens spawning from a mothership in the center of the continent, the attack ending at the end of the day or when the mothership is destroyed (it would have like 500k armor and have massivlly damaging attacks) im not saying to make the 3 factions be allied against aliens (and they cant access sanctuarys) That. Would. Be. Awesome.