User blog comment:Spetsnaz117/Who would win? A Chimeran Titan from Resistance 2 or a Covenant Hunter from Halo 3?/@comment-422690-20100529202519

On the "biologically possible" topic:

The creation of the Chimera is completely and utterly possible with today's human science. Natural parisites already exist that distort their host's shape, so all it would take is to modify that parasite to have an increadibly increased rate of evolution (leading to sapience (different from sentience; spaience means capable of at least some higher thought, sentience could mean even a basic animal)), specialized physcal mutations, and other various possibilites. Their weapons, however, are a different story, though it is possible that they exist on another planet, as Ravager134K mentioned.