# Does a card that affects 'each' creature affect creatures that enter the battlefield after it resolves?

My opponent casts Predatory Rampage, which resolves, then he attacks with his creatures.

In my hand, I have a creature card with Flash. If I summon this creature before the declare blockers step, will it be affected by Predatory Rampage's blocking requirement?

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Welcome to B&CG! – Pat Ludwig Jan 14 '13 at 6:30
I think the answer is yes, but if you don't want to block with it, why wouldn't you wait until the Combat phase is over before casting it? :) – ghoppe Jan 14 '13 at 6:32
ghoppe, the actual situation was that I had a Cloudshift and wanted to use it to save one of my creatures from blocking. Obviously I just declared it as a blocker then Cloudshifted, but I was very curious about the rules anyway. – Glacials Jan 14 '13 at 8:05

Yes.

That's an easy one, as it is in the Gatherer rulings:

Each creature your opponents control blocks if able, even if that creature wasn't on the battlefield or wasn't controlled by an opponent when Predatory Rampage resolved.

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Woops, thanks for this. I need to pay more attention to the rulings! – Glacials Jan 14 '13 at 8:09
While this is true for this example. It's not true as a general rule. Ikegami answer is more complete. – Pablo Mar 3 '14 at 2:56

It varies a lot depending on the specifics.

In the case of Predatory Rampage, we're talking about two continuous effects generated by something other than a static ability. One modifies the characteristics of objects, and the other doesn't. Both of those situations are covered by 611.2c.

611.2c If a continuous effect generated by the resolution of a spell or ability modifies the characteristics or changes the controller of any objects, the set of objects it affects is determined when that continuous effect begins. After that point, the set won’t change. (Note that this works differently than a continuous effect from a static ability.) A continuous effect generated by the resolution of a spell or ability that doesn’t modify the characteristics or change the controller of any objects modifies the rules of the game, so it can affect objects that weren’t affected when that continuous effect began.

As such,

• "Creatures you control get +3/+3 until end of turn." affects only the creatures that existed when Predatory Rampage resolved.
• "Each creature your opponents control blocks this turn if able." affects all matching creatures at all times.

Both of these are covered by rulings in Gatherer.

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For completeness: "An object’s characteristics are name, mana cost, color, color indicator, card type, subtype, supertype, rules text, abilities, power, toughness, loyalty, hand modifier, and life modifier. Objects can have some or all of these characteristics. Any other information about an object isn’t a characteristic. For example, characteristics don’t include whether a permanent is tapped, a spell’s target, an object’s owner or controller, what an Aura enchants, and so on." – Jefromi Dec 27 '15 at 2:54

I trawled the Comprehensive Rules for an authoritative answer to this excellent question (the ruling on Predatory Rampage may say how it works, but it doesn't say why it works!) and I think the following rule explains all. Bolded by me for emphasis of the most important line:

611.2c If a continuous effect generated by the resolution of a spell or ability modifies the characteristics or changes the controller of any objects, the set of objects it affects is determined when that continuous effect begins. After that point, the set won't change. (Note that this works differently than a continuous effect from a static ability.) A continuous effect generated by the resolution of a spell or ability that doesn't modify the characteristics or change the controller of any objects modifies the rules of the game, so it can affect objects that weren't affected when that continuous effect began.

Example: An effect that reads "All white creatures get +1/+1 until end of turn" gives the bonus to all permanents that are white creatures when the spell or ability resolves -- even if they change color later -- and doesn't affect those that enter the battlefield or turn white afterward. Example: An effect that reads "Prevent all damage creatures would deal this turn" doesn't modify any object's characteristics, so it's modifying the rules of the game. That means the effect will apply even to damage from creatures that weren't on the battlefield when the continuous effect began. It also affects damage from permanents that become creatures later in the turn.

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Interesting that "All white creatures get +1/+1" and "All white creatures get +1/+1 until end of turn" behave differently with respect to newly created creatures! – Nick Jan 14 '13 at 15:59
@Nick: How so? Are you maybe confusing static abilities with continuous modifiers (=a continuous effect generated by the resolution of a spell or ability)? If such an effect had the text "All white creatures get +1/+1", it would work exactly the same way "All white creatures get +1/+1 until end of turn" does, except for the fact it wouldn't end at the end of the turn. – scenia Mar 3 '14 at 17:41
@scenia Well yes, I meant a permanent with +1/+1 to all affects newly created creatures afterwards, but a +1/+1 until end of turn instant will not affect newly created creatures. – Nick Mar 3 '14 at 23:48
@Nick Thought so. The difference there (or rather, the thing that makes a difference) is not the "until end of turn", but the fact one is a permanent and the other an instant. The instant creates a modifier that is placed onto all currently eligible creatures. Then it's done and doesn't care what happens any more. The permanent, on the other hand, constantly applies its effect as long as it's in play. If a new creature appears that meets the criteria, since the permanent is in play, it will be affected. If the permanent leaves play somehow, the effect immediately stops on all creatures. – scenia Mar 4 '14 at 8:19