Some knowledge of synths, LFO, modulation, automation.
Drums that fit in context...optional samples. The Daw is probably the last thing you need to worry about to make Dubstep any genre at that unless you depend on a score sheet...long as it has basic stuff which is hard not to find in a Daw honestly... you'll be fine try em out and choose whats comfortable for you. Its up to you to learn your tools and to make it sound good. That said everything already mentioned in above posts, so you have plenty of options and a bunch of opinions to decide.