For newer players, what that means is that if you tap a Forest for a mana you can get another Green mana, but if you tap something like a Watery Grave for a Blue mana, you can also get one Black mana for free
Call to the Netherworld At first the card appears strictly superior to Grave Scrabbler, but this card is useless to cast without a creature in our graveyard and doesn't provide a blocker for us, so
Could blue be relegated to the role of support colour like it kind of was in Brothers' War
Miraidon ex 081/198 Loading
Rather than having triggers that toggled things back and forth, they needed to have a single trigger that made it Night, but only for a certain duration
So, as you add scroll counters to Aretopolis, you either gain life equal to the number of scroll counters, or chaos add a counter and draw cards