Upon crash landing on Cradle, instead of trying to make peace with the Gremlins, which are Natives to the Cradle, we decide to annihilate their species. When you reach a foreign place, it would be wise to seek help from the locals, but what do the Spirals decide to do? Kill them all, take their crystals, dig deeper into their planet
As the invaders, we don't really see what the higher ups had planned. Sure, get the crystals and dig deeper, try and find some more neat stuff, but in reality when we get down to those levels we are the monsters
The gremlins made the twins as a means on self defense for the invaders that have begun to strip their planet of resources.
Instead of asking them for help, seeing how they are intelligent enough to construct the twins and other means of weaponry, we decide to kill them on site and dig deeper into their planet so we can suck it dry for ourselves before "crash landing" on to the next planet. Yes, the perfect plan...
All hail the spirals!
How do we know heat isn't the equivalent of blood to the creatures on Cradle. If so not only are we destroying them but we're using their blood to power our armor and weapons.