I have the bade, got it a while ago (on MY account, GnomeSlice). The trick is to get the area where its all flat. On the far right thers a stack of boxes, and s platforms going up, then a second floor. You stand on the first platform and you can shoot down through it at baddies, or jump and shoot up through it. Every now and then run up or down wid a gauss, just in case you missed some, and grab all the guns and powerups. Worked for GnomeSlice anyway ;)
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