Tactics: A time to attack or a time to defend?

The 11th Edmonton International is on this week, and once again it is set to be Canada's strongest round robin of the year. It gives Canadian FMs and IMs a chance to earn Norms against world-class GMs from around the world. This year, the GMs are: Alexei Shirov (LAT), Surya Ganguly (IND), S P Sethuraman (IND, 2016 Asian Champion), Sam Shankland (USA), and Bator Sambuev (CAN). The players hoping for normas are: IM Richard Wang (CAN) and FMs Ian Findlay (CAN), Dale Haessel (CAN), Bitan Banerjee (IND), Belsar Valencia (PHIL).

You can follow the games here:
http://edmonton-international.com/

Today's Canadian Tactic of the Week is from the round 1 game between FMs Haessel and Findlay.
Black is up two pawns, but his Bg2 is offside and both Kings are under pressure. What should Black play?

Solution: see the game below. 

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 Round:  Result:

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