Pillage the Bog states if you cast this card with the Plotted Emblem, the last 4 cards in hand gain mana equal to the number of Lands and their reinforcements you control plus 3.
Pillage the Bog’s effect only gives mana equal to the number of Lands and their reinforcements you control. It does not give the +3. I cast it with no Land Supports and it gave no Mana. Then I cast it with 1 land with a reinforcement, and my cards got 2 mana each.