First of all, I know this is a dirty way of playing, and I'll only do it if I really need to.
I play Bogles, where you take a 1/1 hexproof and stack a bunch of auras on it to make it really scary, with Ethereal Armor, Daybreak Coronet, Rancor etc. As a result, the power and toughness are kinda hard to calculate, especially with Ethereal Armor counting other auras and Rancor adding power but not toughness. It's pretty common for people to not realize Ethereal Armor counts Leyline of Sanctity or forget about Kor Spiritdancer's passive buff. All of the online guides I read said "never calculate it for your opponent, because if they declare no blocks then die instantly that's game, and the judge will back you up."
The battlefield is public information, but do I have to do the math? If I refused, I'd have to let them pick up my 7-card stack of auras and figure it out for thmeselves, but is it still possible? The first time I tried that stunt, my opponent got very frustrated and said "okay, then I take 5" when my boyo was clearly stronger than that.
And I assume it's a big no-no to lie about his power to get them to block badly.
Private Mod Note
():
Rollback Post to RevisionRollBack
"Life is a jape. Yours, mine, everyone's."
—Tyrion Lannister, A Dance with Dragons
At regular REL (rules enforcement level), derived information is treated as free information, so at FNM and similarly low level events you have to tell your opponent, yes, and it has to be true. At a higher REL, they have to figure it out themselves, though you are of course free to help them do that if you wish. However, the actual damage dealt must be correct, you cannot let your opponent take more or less damage just because they miscalculate, or you miscalculate. If they or you make a calculation error, the other player has to step in and correct it. Because the game state has to be kept clear and correct by all players.
At regular REL (rules enforcement level), derived information is treated as free information, so at FNM and similarly low level events you have to tell your opponent, yes. At a higher REL, they have to figure it out themselves, though you are of course free to help them do that if you wish. However, the actual damage dealt must be correct, you cannot let your opponent take more or less damage just because they miscalculate, or you miscalculate. If they or you make a calculation error, the other player has to step in and correct it. Because a player's life total is free information at every REL.
Thank you!
Private Mod Note
():
Rollback Post to RevisionRollBack
"Life is a jape. Yours, mine, everyone's."
—Tyrion Lannister, A Dance with Dragons
There are a couple different answers here depending on the exact situation.
To start with, it is important to recognize the different types of information that exist within Magic. There is Hidden, Free, and Derived, and Status information. So, to get to the root of what you can and can't do, you need to recognize what "Power/toughness of a creature" falls under.
We will focus on Free and Derived as those are the ones that matter here. Here is the description for free:
Details of current game actions and past game actions that still affect the game state.
The name of any visible object.
The number and type of any counter that isn’t defined as status information.
The state (whether it’s tapped, attached to another permanent, face down, etc.) and current zone of any object or player.
The game score of the current match.
The current step and/or phase and which player(s) are active.
And Derived:
The number of any type of objects present in any game zone that are not defined as free information.
All characteristics of objects in public zones that are not defined as free or status information.
Game Rules, Tournament Policy, Oracle content and any other official information pertaining to the current tournament. Cards are considered to have their Oracle text printed on them.
Now, you will notice the line about "all characteristics of objects...." and the P/T of a creature is not defined as being free information. So, from here you can determine that the information your opponent is looking for is Derived information. And the rules for Derived information are:
Players may not represent derived, free, or status information incorrectly.
Players must answer completely and honestly any specific questions pertaining to free information.
At Regular Rules Enforcement Level, all derived information is instead considered free.
So, from here we can see that only Free information needs to be answered completely and honestly but derived cannot be represented incorrectly. What this means is that for derived information "you figure it out" is fine (though I might suggest a better way to say it) but you cannot lie about it and give them a false answer.
Importantly though, this only applies at Comp REL. At regular REL (prereleases and FNM for example) we can see there is no derived information. Instead, all of that falls under free. So, if you are playing at FNM, you must answer your opponent, and answer honestly, but at comp you can refuse to answer since they should be able to find out.
I play Bogles, where you take a 1/1 hexproof and stack a bunch of auras on it to make it really scary, with Ethereal Armor, Daybreak Coronet, Rancor etc. As a result, the power and toughness are kinda hard to calculate, especially with Ethereal Armor counting other auras and Rancor adding power but not toughness. It's pretty common for people to not realize Ethereal Armor counts Leyline of Sanctity or forget about Kor Spiritdancer's passive buff. All of the online guides I read said "never calculate it for your opponent, because if they declare no blocks then die instantly that's game, and the judge will back you up."
The battlefield is public information, but do I have to do the math? If I refused, I'd have to let them pick up my 7-card stack of auras and figure it out for thmeselves, but is it still possible? The first time I tried that stunt, my opponent got very frustrated and said "okay, then I take 5" when my boyo was clearly stronger than that.
And I assume it's a big no-no to lie about his power to get them to block badly.
"Life is a jape. Yours, mine, everyone's."
—Tyrion Lannister, A Dance with Dragons
Former Rules Advisor
"Everything's better with pirates." - Lodge
(The Gamers: Dorkness Rising)
"Any sufficiently analyzed magic is indistinguishable from science."
(Girl Genius - Fairy Tale Theater Break - Cinderella, end of volume 8)
Thank you!
"Life is a jape. Yours, mine, everyone's."
—Tyrion Lannister, A Dance with Dragons
To start with, it is important to recognize the different types of information that exist within Magic. There is Hidden, Free, and Derived, and Status information. So, to get to the root of what you can and can't do, you need to recognize what "Power/toughness of a creature" falls under.
We will focus on Free and Derived as those are the ones that matter here. Here is the description for free:
The name of any visible object.
The number and type of any counter that isn’t defined as status information.
The state (whether it’s tapped, attached to another permanent, face down, etc.) and current zone of any object or player.
The game score of the current match.
The current step and/or phase and which player(s) are active.
And Derived:
The number of any type of objects present in any game zone that are not defined as free information.
All characteristics of objects in public zones that are not defined as free or status information.
Game Rules, Tournament Policy, Oracle content and any other official information pertaining to the current tournament. Cards are considered to have their Oracle text printed on them.
Now, you will notice the line about "all characteristics of objects...." and the P/T of a creature is not defined as being free information. So, from here you can determine that the information your opponent is looking for is Derived information. And the rules for Derived information are:
Players must answer completely and honestly any specific questions pertaining to free information.
At Regular Rules Enforcement Level, all derived information is instead considered free.
So, from here we can see that only Free information needs to be answered completely and honestly but derived cannot be represented incorrectly. What this means is that for derived information "you figure it out" is fine (though I might suggest a better way to say it) but you cannot lie about it and give them a false answer.
Importantly though, this only applies at Comp REL. At regular REL (prereleases and FNM for example) we can see there is no derived information. Instead, all of that falls under free. So, if you are playing at FNM, you must answer your opponent, and answer honestly, but at comp you can refuse to answer since they should be able to find out.