I'm on the same page as Konrad. I've attempted to "earnestly study this matter" and found no rules texts that would override the quoted The Balrog clarification. It stipulates three requirements for its implication:
- card is a hazard permanent event
- card indicates "kill" marshalling points
- card has an attack associated with it
Spider of Morlat achieves all of these requirements. Therefore, if its permanent-event attack is defeated, "treat the associated card as a defeated creature." Wizard or Fallen Wizard resource players (for whom the attack is not detainment) can thus receive the card's MP.
I have been told that this is not how this card is typically played by most groups. However, arguments such as "I think it's pretty clear", "if the attack you defeated has the prowess and body listed in the lower left hand corner of the card you get the MPs", "this is how I've played for 20 years", and "4 MP is too much for defeating a 3@10 attack" are indeed nowhere in the official rules and not a sufficient basis for universal understanding/enforcement.
I am very interested in any official rules texts that would shed new insight into this matter (the upcoming 2019 ARV may be a good option). Until that time, I find no ambiguity to argue against a player defeating the permanent-event attack receiving the card's MP, house rules aside.
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