Reploids

reploids are liquid metal robots that the president commisiont for world domination.

they are indistructible, as a blow to the body would damage them but they would just reform.

their liquid metal body allows them to change into anybody making it hard to distinguish them from other people. only Emmett has the technology to notice them.

magenets can tamper with their structure, temperarily freezing them.

a blow to the head could destroy them causing them to melt due to their brain chip being destroyed.