QUESTION: If swords of revealing light is already activated and my opponent summons the Winged Dragon of Ra,during the second or third turn of its effect, does it negate swords of revealing light? I thought Ra only prevented the activation of new cards.
ANSWER: Hey Jose,
Thank you for the question, in my opinion Winged Dragon of Ra can't negate swords of revealing light since it has already been activated which means the effect went through; Ra only prevents you to negate cards activated after his summon during that turn. I have checked with many people on this ruling and I basically keep getting the same answer. I hope this helps your situation.
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QUESTION: What happens to my opponent if I have to Magicians Valkyria on the field? Would it create a never ending chain to prevent my opponent from attacking because her affect is your opponent cannot attack any other face up spellcaster monsters except this one. So the effects would just jump the attack back and forth to each other.
You are correct it would create a never ending chain since you have 2 Valkyria's on the field; it creates 2 effects combined to one. For Example if you have 2 Marauding Captain's on the field your opponent can't attack any of them since they both have the same effect(the opponent cannot attack any face-up Warrior-Type monsters you control.) Hope this clears your situation.