k so GG engineers was a joke for me once I figure out an easy strat.
At the start run up where they spawn (start on the right guy),pop everything and spread a big combust. When they teleport stick on the death ray guy and interrupt him as much as possible. When you get low ice block/cold snap and sit on top of him and let the rockets take him down. When you get low again go inside the next shield that comes up and evocate to full. After that they were almost dead and I finished them off in ice block with rockets. Currently on Battletron now and should get him in the next attempt.