I have an issue with Gleba..

I was playing through, just got some chemical science, landed on Gleba. During the first wave, small flying enemies came along, who wouldn't be targeted by my guns, making them effectively Immortal.

They had around 30 health, 5 damage, and did a small laser as attack. They had a weird name, like it wasn't a display name but one used in code without spaces, similar to the platform accumulator

Anyone know what it was?

Nevermind. I just found out that for some reason it downloaded Warptorio version 0.0.17 into my Factorio. Playing again now with the new version..

even in 0.0.17 they should not be imune to damage. Maybe you had turrets set to specific targets?