Infernal DarknessHow it works & interactions with other cards

What It Does

Infernal Darkness creates a replacement effect that modifies what happens when a land is tapped for mana. Instead of producing its normal color or type of mana, the land produces black mana ({B}) instead. This affects all players, including you. The amount of mana produced remains the same; only the color is changed. Additionally, it features Cumulative Upkeep, meaning it becomes increasingly expensive to maintain each turn.

How It Resolves Step by Step

When your upkeep begins, the Cumulative Upkeep trigger goes on the stack. First, you put an age counter on Infernal Darkness. Second, you must choose whether to pay the cost—one black mana and 1 life—for each age counter currently on the card. If you cannot or choose not to pay the total accumulated cost, you must sacrifice the enchantment. Once it is on the battlefield, the mana-changing effect is continuous and does not use the stack.

Common Mistakes

A common misconception is that Infernal Darkness reduces the amount of mana a land produces. If a land naturally produces two mana of a specific color, such as {W}{W}, Infernal Darkness ensures it produces {B}{B} instead. Another mistake is forgetting that the life payment is part of the Cumulative Upkeep cost. Because this cost increases every turn, you must carefully manage your life total alongside your mana pool to keep the lock active.

When to Play It

Infernal Darkness is best deployed when you are ahead on board or playing a mono-black deck that isn't hindered by the color restriction. It is particularly devastating against three-color or five-color decks that require specific mana fixing to cast their spells. Timing it right after your opponents have tapped out can prevent them from casting reactive spells on your turn.

Interaction examples

Managing the Upkeep Cost

Phyrexian Arena

During your upkeep, both Phyrexian Arena and Infernal Darkness will trigger. You can choose the order. If you resolve Phyrexian Arena first, you draw a card and lose 1 life, then you proceed to the Cumulative Upkeep of Infernal Darkness. Note that the life loss from both cards can add up quickly, so you must ensure you have enough life to pay for the age counters to keep the mana lock in place.

Generating Resources Under the Lock

Black Market Connections

While Infernal Darkness restricts your lands to producing black mana, Black Market Connections triggers at the start of your precombat main phase. The Treasure tokens created by the 'Sell Contraband' mode will still be able to produce any color of mana when sacrificed, because Infernal Darkness only affects lands being tapped for mana, not artifacts or other non-land sources.