I control Thantis, the Wareaver and Master of Cruelties. When I enter into my combat phase, how do these interact? Would Thantis force me to attack with everything, which means Master of Cruelties can't attack?
Thantis, the Warweaver
Everything but Master of Cruelties will be forced to attack assuming you have no other attack restrictions. The reason is kind of long and complicated but here is the rule.
508.1d The active player checks each creature they control to see whether it’s affected by any requirements (effects that say a creature attacks if able, or that it attacks if some condition is met). If the number of requirements that are being obeyed is fewer than the maximum possible number of requirements that could be obeyed without disobeying any restrictions, the declaration of attackers is illegal. If a creature can’t attack unless a player pays a cost, that player is not required to pay that cost, even if attacking with that creature would increase the number of requirements being obeyed. If a requirement that says a creature attacks if able during a certain turn refers to a turn with multiple combat phases, the creature attacks if able during each declare attackers step in that turn.
...and also rule 508.1c.
The rule of thumbs for this kind of situation is thus:
-one cannot, ever, tresspass a RESTRICTION (rule 508.1c), which is why Master of Cruelties cannot, ever, attack along with other creatures.
-one must try and maximize the number of satisfied REQUIREMENTS (rule 508.1d): each creature you control is subjected to Thantis' requirement to attack, thus each creature counts as one requirement asking to be fullfilled.
If you have 3 or more creatures, sending Master of Cruelties would fullfill only one requirement, while sending the others would fullfill more than one, which is why MoC must stay home in such case.
508.1c (…) If any restrictions are being disobeyed, the declaration of attackers is illegal.
508.1d (…) If the number of requirements that are being obeyed is fewer than the maximum possible number of requirements that could be obeyed without disobeying any restrictions, the declaration of attackers is illegal. (…)
I control Thantis, the Wareaver and Master of Cruelties. When I enter into my combat phase, how do these interact? Would Thantis force me to attack with everything, which means Master of Cruelties can't attack?
Thank you yall.
Everything but Master of Cruelties will be forced to attack assuming you have no other attack restrictions. The reason is kind of long and complicated but here is the rule.
508.1d The active player checks each creature they control to see whether it’s affected by any requirements (effects that say a creature attacks if able, or that it attacks if some condition is met). If the number of requirements that are being obeyed is fewer than the maximum possible number of requirements that could be obeyed without disobeying any restrictions, the declaration of attackers is illegal. If a creature can’t attack unless a player pays a cost, that player is not required to pay that cost, even if attacking with that creature would increase the number of requirements being obeyed. If a requirement that says a creature attacks if able during a certain turn refers to a turn with multiple combat phases, the creature attacks if able during each declare attackers step in that turn.
The rule of thumbs for this kind of situation is thus:
-one cannot, ever, tresspass a RESTRICTION (rule 508.1c), which is why Master of Cruelties cannot, ever, attack along with other creatures.
-one must try and maximize the number of satisfied REQUIREMENTS (rule 508.1d): each creature you control is subjected to Thantis' requirement to attack, thus each creature counts as one requirement asking to be fullfilled.
If you have only 2 creatures (Master of Cruelties and Thantis, the Warweaver), you'll have to send one or the other, fullfilling one of two requirements.
If you have 3 or more creatures, sending Master of Cruelties would fullfill only one requirement, while sending the others would fullfill more than one, which is why MoC must stay home in such case.
508.1d (…) If the number of requirements that are being obeyed is fewer than the maximum possible number of requirements that could be obeyed without disobeying any restrictions, the declaration of attackers is illegal. (…)
Similar rules exist for blocking.
RULES OF MAGIC :
http://magic.wizards.com/en/game-info/gameplay/rules-and-formats/rules
MoC is the only creature that can legally be declared an attacker: You must attack with MoC.
There are exactly two creatures, one of which is MoC, that can attack: You must attack with one of the creatures. It is your choice.
There are 3+ creatures including MoC that can attack: You must attack with all creatures except MoC.