What are the Comprehensive Rules? Magic is complicated. No, really. When you have more than 13,000 interchangeable game pieces, you get some freaky interactions. The Comprehensive Rules cover everything the game has ever come up with, from basic game play structure, to every keyword ever, to entire pages dedicated to single bizarre cards (hello, Karn Liberated!). The Comprehensive Rules are, well, comprehensive…but they're also obtuse, unfriendly, and looooong. They're not intended to be a player resource—they're a judge resource, a rules guru resource, and a place to store definitive answers. In fact, I honestly recommend never reading them. For a much friendlier rulebook that is intended to be a player resource, check out the Rules Page and download the Basic Rulebook (4.37 MB PDF). It doesn't have sections about phasing or subgames…but you'll never miss them.

106.10a

This is a new rule that slightly changes how we resolve abilities that trigger whenever a permanent is tapped for mana or for mana of a specified type. Now, you look at what was actually produced after the activated mana ability resolves. So, tapping a Gaea's Cradle while you no control no creatures won't cause a Wild Growth attached to it to trigger. The good news is it's now clear if you named blue for Gauntlet of Power, tapping a Mountain that produces {U} because of a replacement effect will cause it to trigger. Let the deckbuilding begin!

107.12

The chaos symbol is now louder. {CHAOS}! This change pops up in a few other rules as well.

107.13 and 107.14

The rules defining the sun and moon symbols have been deleted. The symbols used by the Magic Origins double-faced cards obviously aren't a sun and moon. Amusingly, one of the symbols is the Planeswalker symbol, and that has some complications of its own. So, those symbols are now just decorative and the front face of a double-faced card is defined as the one with the mana cost. Surely this fix will last forever and ever and won't need to be changed.

207.2c

Spell mastery is added to the list of ability words. (Ability phrases?)

400.4b

This rule stops certain card types from leaving the command zone. I forgot to put Conspiracies on this list. Oops!

408.3

Conspiracy Draft was missing from the list of formats and variants that make use of the command zone. Oops!

509.1c

This rule explains how requirements and restrictions affect your choice when attacking or blocking. It included an example featuring a creature that can't be blocked except by two or more creatures. Now that menace exists, I rewrote the example slightly.

601.2 and subrules

I made some tweaks to the procedure of casting a spell or activating an ability. It basically boils down to the proposal of the spell, including making all necessary choices such as modes and targets. Then the game checks to see if what you've proposed is legal. Finally, assuming the spell is legal, you calculate and pay costs. In practice, not much is changing. Bestow gets a little easier to figure out. For example, if an effect stops you from casting creature spells, you can still cast one as an Aura. There are some strange cases with things like split cards or flash that become a bit clearer as well.

601.5

We've deleted this rule that says you can't begin to cast a spell that's prohibited from being cast. The legality check now happens at one defined point, according to the changes to rule 601.2. Technically, you can begin to cast a spell whose been named for Meddling Mage, for example, but you won't get very far before the game detects this illegal action and backs up. In practice, nothing really changes.

603.6d

Erebos's Titan has an ability that triggers whenever a creature card leaves an opponent's graveyard. Just like a leaves-the-battlefield triggered ability, this ability must "look back in time" to the moment before the ability triggered to determine the characteristics of the object that left the graveyard. This rule includes the list of abilities that behave this way, and "abilities that trigger when a card leaves a graveyard" was added to it.

608.2b

I made some revisions to this rule, which describes how a resolving spell or ability interacts with illegal targets. If a spell has multiple targets, and some (but not all) of its targets are made illegal, the spell will still resolve, but it won't affect illegal targets in any way. It can't perform actions on an illegal target, have that target perform actions, or cause anything else to perform actions on it. It the spell changes the game rules, those changes don't apply to the illegal target. And if the spell needs information from the target, it can't do anything that relies on that information.

613.6 and subrules

These rules describe the timestamp system that is (infrequently) used to determine how continuous effects interact. It's mostly just a reorganization, but there are new rules to give a permanent a new timestamp when it turns face up or face down. Also, a double-faced card gets a new timestamp when it transforms. And finally, a face-down Conspiracy gets a new timestamp when it turns face up.

701.16c

This rule describes what happens when you're told to shuffle specific objects into your library and none of those objects are there or they would move somewhere else because of a replacement effect. Under old rules, you wouldn't shuffle your library, but that's changing. Now, if the effect says to shuffle something into your library, you shuffle even if no cards are being added to your library. (Don't confuse this with a spell or ability that doesn't resolve. An Oblation with a missing target will be countered and you won't shuffle your library.)

701.28b

Monstrous and renowned have a lot in common, so this rule that describes monstrous was tweaked to use a lot of the same language.

702.57

This rule for graft referred to a creature having multiple instances of graft, but really it should say "permanent."

702.102c

The rules for casting a spell with bestow got a slight rewrite alongside the changes to 601.2.

702.110

These are the new rules for menace.

702.111

These are the new rules for renown.

713.1

This new rule explains a bit more about Day's Undoing and ending the turn. Day's Undoing is the first card that has additional effects before it ends the turn. If any abilities trigger while players are shuffling or drawing cards, before the "end the turn" procedure starts, those abilities won't be put onto the stack. The "end the turn" procedure will essentially eat them. Of course, abilities that trigger during the "end the turn" procedure will go on the stack during that turn's cleanup step. (These abilities are pretty rare though.)

903.11

This is Commander's new "tuck rule." A commander that's exiled or put into your hand, graveyard, or library from anywhere can be put into the command zone instead.

Glossary

New glossary entries: menace, renown

Removed glossary entries: moon symbol, sun symbol

Introduction

Oracle Changes

Comprehensive Rule Changes