Verified answer

There aren't really any bosses for that low lvled..ur gonna need atleast 60+atk, and 70+ str to make good slayer vids. if u still want to make vids, try talking to a slayer master and do the tasks he gives you

Adre is right, though at that level it may be possible to kill the King Black Dragon if you know your way around combat. That's still a stretch though.

With those stats, i'd say King Black Dragon. But you might need a few people, if you need ill join your team.