I'm a science fiction writer trying to create a realistic science fiction monster. The base idea is that it's a form of animate carbon that, when given enough mass, is capable of simple locomotion. If it comes into contact with something with carbon in it (anything from carbon-steel to carbon-based life) it strips away the carbon atoms of that something and assimilates them into itself kind of like "gray goo."
However, to be realistic I want to better understand carbon and how it bonds with things. For example, I know that carbon is good at bonding with things, but I don't know what temperatures or situations are required for it to bond with something like nitrogen, oxygen, or other gasses and things it would come into contact with in a pressurized environment. The monster would should have a limited ability to resist bonding with non-carbon atoms if it had enough mass, but one way to defeat it would be to crank up the pressure and/or heat to overcome or "denature" its ability to bond with other atoms.