Riven is a champion that I think to be awesome as a tanky dps. She has a great early game with decent harass from her skills and a decently strong shield, a pretty good mid game with her excellent team play capabilities, and late game functionality as a survivable damage dealer or initiator.

This Riven build requires you to be fairly aggressive. However, "aggressive" does not mean "stupidly charge opponent". It means making fights happen. Smart, calculated fights. Under this playstyle, you have a decent chance of dying under focus fire, but if you are smart about it, your one death will mean four of theirs.

Greater Mark of Strength - These will give you a good early game boost, and with the ArPen masteries and strong scaling on Riven's skills, these are the strongest choice.

Greater Glyph of Shielding - Scaling MR. Equal benefit at around level 6, I believe. These make an excellent substitute for your CDR glyphs. These are generally better than flat MR, unless you are laning against a magic dealer top. Even then, these are probably still better than flat. Your call.

Greater Quintessence of Strength - Once again, Riven's scaling makes these the best choice. The same rules of the marks apply to the quints.

Pros:

High mobility
Shield that increases in strength with AD
Damaging AOE stun
Manaless champ
Insane early damage


Cons:

Needs proper timing on her skills to be effective
Cooldown dependent
A bad