How does Leo save his friends in this section?

Leo sneaks into the factory and sees Piper and Jason hung up by chains suspended from cranes. Around them are three Cyclopes who are planning on cooking and eating them. He quickly throws together a universal remote and uses it to control the cranes so they hit and kill the two brother Cyclopes. The mother is quicker and tougher, but eventually Leo uses his fire to break a link in the chain above her head, sending an engine block crashing onto her head.