You'll likely get this without a guide, but if you are curious on how to get this you'll need to start smashing everything in sight. There are no comic stacks in issues 1 or 6 so the first chance you can start to earn this is in Issue 2.
I'll list the first 5, but you'll eventually need to get them all to unlock the following achievement:
1. On the roof
2. The room with all the elevators
3. 2nd area of the laser trap with Modok
4. In the room with a square platform in the middle there is a stack in the bottom left corner. You have to bomb an obstruction to get to this one.
5. In the office area you'll have to bomb a reinforced door. In here is a secret room with a Comic stack on the far right.