I need a rules clarification. The Blackfish has a Response that reads "After you win a military challenge as the attacker, draw 1 card." Does this affect go off after The Blackfish wins a military challenge, or is it just when the owner wins a military challenge? Can I win a military challenge without The Blackfish's involvement and then set off his response?

Any time an ability uses the word "you", it refers to the controller of the card. So in this instance, you could win a military challenge (on attack), with or without the Blackfish's involvement, and be able to draw a card.

(If they wanted to require the Blackfish to participate, they'd word it "After you win a challenge in which the Blackfish participated, ..." That kind of text is quite common.)