Feral dragons should be those that look like this:
>>60721t >>60646t >>56535t "[![full](https://derpicdn.net/img/2015/5/18/899340/small.png!":)](https://derpibooru.org/images/899340
)
If they walk on two legs they should be anthro or semi-anthro. Semi-anthro for those that don't look much like humans, I would say forms like this:
>>24815t >>41299t
And this should be anthro
>>57850t >>42122t
I'm not so sure about
>>51660t >>11852t
They bodies are not quite human-shaped like for example it is here:
>>50411t
But they still have something that looks more like hands than another pair of feet as front limbs.