oh, that! well, when both cards have the same attack value, the card with the lower star count wins, e.g. 5* with 42 attack, 4* with 42 attack, 4* card wins. if both have the same attack value and the same star count, the card which was played first wins.
oh i forgot the fact that you mention that you play at "any" style. using "any" as a preference means you can face players using both "normal" and "no random" mode. the one i stated always works on "no random" mode. luck plays a big big factor in "normal" mode. but, again, there is no such thing as a luck stat attached to a clan, so the Junkz losing all the time just means you lose by random.