im ordering c99x blueberry hehe, um i would say a strain is a scientific classification, at some point down the line from a species. There are so many though, in all seriousness anything you do to alter a strain cross bread... will create a new strain, but how you go about it is how it becomes a relitavly popular strain, if i cross something thats been done before and has a name like white rhino, then i am just takeing the long way to making white rhino. crossing hybrids works, it really doesnt matter, a new strain comes from something never crossed before. its easy to make your own strain, but to have it noticed by ppl may be hard. i would take alot of necessary precautions to do this. it also could take a while to perfect your strain, thats why u would want to be carefull and save seeds keep mothers of different generations. its a process if your going to do it right.