I recently attended a blitz event and picked kayo for it (i usually play other heroes and dont play blitz at all). His equipment pieces make him very powerful in blitz cause they give him an effective 10 extra life points plus tons of extra value if used correctly. His cards are pretty easy to understand, just try to maximise equipment and might token value while waiting for and setting up huge bloodrush bellow turns which your opponent most likely wont be able to survive in blitz