Just weird generation. I am in a game now where most shields have a base charge of 20. I've only seen like 2 with 10 shield. It's just what happened on your map, it's not really a bug.
My faith has found a resting place,
Not in device or creed;
I trust the ever-living One,
His wounds for me shall plead.
I need no other argument,
I need no other plea,
It is enough that Jesus died,
And that He died for me.