Introduction
Terraforming Mars has an important player mat that has tracks to record the production and amount of a number of resources. Unfortunately, it is easily knocked and thus the game is affected. I found this overlay that cleverly uses a bit of printed paper and wedges it in a well with a small grid overlay for the cubes. I did use a bit of PVA to ensure the grids did not pop out. And as of current I haven’t added the photo corners yet to secure the mat to the back.
Pictures
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Single Overlay

5 Overlays