I know some folks will print cards on heavy card stock and then cut them out, even rounding the corners
Then, whenever you amass while controlling an Army, you put the +1/+1 counters on the existing Zombie Army creature token
Then the seven-drop has living weapon and gives a +5/+5 size, first strike, indestructible (has it itself), and trample and then the combat damage trigger to exile what was killed
The drawback isnt as bad as it looks, and the downside will likely be turning Call of the Full Moon into a two-mana Lava Spike with some chance of repeating
MTG Playmats Specifications
His input was especially important toward the end of the process, where we iterate on card designs and power levels based on play design's testing