Terry Westley's side started the game at a rain soaked St Andrews brightly and took a fifth minute lead through Robin Shroot.
Blues doubled their advantage ten minutes before the half time interval when Shroot scored his second of the night.
Five minutes into the second half Villa reduced the deficit to 1-2 when Andreas Weimann pulled a goal back for the visitors.
Villa drew level after 65 minutes, Weimann the goalscorer again, and things got worse for Blues just two minutes later when Marc Albrighton's intended cross was defelected past keeper Joe Hart by Giovanny Espinoza to give the Villa a 3-2 lead.
However, Kevin Phillips salvaged a point for Blues with a deserved equaliser five minutes from time.
In the dying moments Blues defender Jacob Rowe was sent off for a second yellow card offence.
Villa Res: Elliot Parish, Matthew Roome, Derrick Williams, Jonathan Hogg, Ciaran Clark, Nathan Baker, Marc Albrighton, Andreas Weimann, Nathan Delfouneso, Barry Bannan, Gary Gardner. Subs: William Grocott, Thomas Dau, Andras Stieber, Harry Forrester, Adam McGurk.