Light of Day is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Black creatures can't attack or block.

Complete guide

Light of Day is a powerful classic enchantment that acts as a definitive hurdle for players relying on the forces of darkness. By fundamentally altering the combat rules for specific creatures, it creates a stagnant battlefield that forces opponents to find non-combat solutions. This guide will explore how this white enchantment effectively shuts down aggressive strategies.

What it Does

Light of Day establishes a continuous effect that modifies the rules of combat. Specifically, it states that black creatures are prohibited from being declared as attackers or blockers. This is a static ability that does not use the stack and remains in effect as long as Light of Day is on the battlefield and the creature in question has the black color identity.

How it Resolves Step by Step

Once Light of Day enters the battlefield, the game state checks the colors of all creatures currently in play. During the Declare Attackers step, if a creature is black, the game rules prevent its controller from selecting it as an attacker. Similarly, during the Declare Blockers step, any creature that is black cannot be assigned to block an incoming threat. If a creature becomes black after it has already been declared as an attacker or blocker, it is not removed from combat, as the restriction only applies to the act of declaring the action.

Common Mistakes

A frequent misconception is that Light of Day prevents black creatures from activated abilities or enters-the-battlefield effects; it does not. It exclusively restricts attacking and blocking. Another mistake is assuming it targets; because the text does not use the word 'target,' it affects creatures with Hexproof or Shroud, and even those with Protection from White, as the enchantment does not target, damage, enchant, or block them.

When to Play It

This card is a specialized tool best used in sideboards or specific metagames where black-heavy decks are prevalent. It is particularly effective against aggressive 'suicide black' or zombie tribal decks that lack enchantment removal, effectively locking them out of the combat phase entirely.

Interaction examples

Layering Defenses

Ghostly Prison

With both enchantments on the field, your opponent faces a double restriction. If they have non-black creatures, they must pay {2} mana for each one they wish to attack you with due to Ghostly Prison. However, if they have black creatures, those creatures cannot attack at all, regardless of whether the opponent has the mana to pay the tax.

Taxing and Locking

Smothering Tithe

In this scenario, Light of Day prevents black creatures from pressuring your life total. While the opponent is stuck searching for an answer, Smothering Tithe punishes them for every card they draw to find that answer. If they spend their mana to prevent you from getting Treasures, they likely won't have the resources to cast the spells needed to remove Light of Day.

Guide written with AI from the official text and rulings. Official English text prevails.