Knowledge Is PowerHow it works & interactions with other cards

A Constant, Shifting Bonus

This enchantment creates a static ability that continuously checks how many cards you have drawn since the current turn began. The value of X starts at zero at the very beginning of the turn and increases by one every time a card enters your hand from your library. Because this is a static effect, the power and toughness of your creatures will update immediately as soon as a draw resolves, without needing to wait for a trigger to go on the stack.

Step-by-Step Resolution

First, the game tracks all cards you have drawn this turn, including your normal draw in the draw step. Second, if you cast a spell or activate an ability that causes you to draw, the number of cards drawn is updated the moment the card is moved to your hand. Third, Knowledge Is Power immediately recalculates X and applies the new +X/+X bonus to all creatures you currently control. This happens even in the middle of resolving a spell if that spell has multiple instructions.

Common Misconceptions

A common mistake is thinking the bonus is 'locked in' once creatures are declared as attackers; it is not. If you draw more cards during the declare blockers step or even in the middle of combat, the creatures' power and toughness will increase instantly. Additionally, note that this only counts cards 'drawn.' Putting a card into your hand from your graveyard or library via a 'tutor' effect that does not use the word 'draw' will not increase the bonus provided by Knowledge Is Power.

When to Play It

Knowledge Is Power is most effective in decks that can draw multiple cards at instant speed. By drawing cards after blockers have been declared, you can surprise your opponent with lethal damage or save your creatures from damage-based removal. It is also highly effective in 'Wheels' decks where you might draw seven or more cards in a single turn, providing a massive +7/+7 boost to your entire board.

Interaction examples

Explosive Combat Draws

Kindred Discovery

With Knowledge Is Power on the field, you play Kindred Discovery and choose 'Human.' When you attack with three Humans, Kindred Discovery triggers three times. As each draw trigger resolves, your creatures each gain an additional +1/+1. By the time the third trigger finishes, every creature you control has received a total of +4/+4 for the turn (including your turn draw), likely overwhelming your opponent's blockers.

Economic Warfare

Smothering Tithe

While Smothering Tithe helps you ramp, it doesn't directly increase the bonus of Knowledge Is Power because your opponents are the ones drawing the cards. However, you can use the Treasure tokens produced by Smothering Tithe to pay for expensive blue draw spells on your own turn. This synergy ensures you have the mana needed to maximize your card draw and, consequently, your creatures' power and toughness.