Amanda Waller in Arrow Season 3
Teaser trailer
https://www.youtube.com/watch?v=DfgthhsuUb8
She appears around the 1:50 mark
http://www.tvguide.com/News/Arrow-Season3-Andrew-Kreisberg-1084620.asp x
There’s also interesting conflict between Dig and Lyla because Lyla is still working at A.R.G.U.S., which we’ve painted as a less than savory organization. That tension between Dig, Lyla and Amanda Waller (Cynthia Addai-Robinson) — as big a part that Amanda is playing in the past, she’s playing just as big a part in the present.
Sounds like she's going to be a semi-regular.