Two-"oh" - SILVER
Thanks for the solid suggestions from basically everybody who chimed in! Will Bumgardner and April King, in particular, immediately hit on some very good things to try right off the bat.
Whenever we're faced with a situation like this, the thing to do is investigate. There's a piece of information we don't know, and our first goal should be to find information we do or can know that will lead us to it. In this situation, there are a number of useful things we can try:
* Asking who went first in game 2 – this often lets us “work backward” to who had the choice, and thus who lost game 1.
* If the players have been recording life totals on paper, look at those and ask questions; often, something as simple as “what caused this loss of two life” can jog a player's memory and get us quality information.
* Ask each player, separately, to ex plain how game 1 ended, and compare the stories. Don't hesitate to use this information for further questions, like “Your opponent says he had this creature and that creature, and you blocked like this when he attacked; does that match what you remember?”
* If you're not getting anywhere with the players, remember there are
other people around. Spectators may have seen what happened, and players at nearby tables may also have information.
Finally, keep in mind that sometimes there will *not* be solid, case-closed evidence one way or another, but you still need to make a ruling. This is where you can tie together all of the above techniques and more; while we always want to have clear evidence to point to, when we don't have that it's OK – if a bit less than ideal – to pay attention to things like who sounds more confident (or the opposite: who sounds more hesitant in recalling things?), whic h player seems to have better or more detailed recall or records of what happened, etc., and make the call that way.
And, as always, bear in mind the time you're spending on the issue; issuing an extra-large time extension and holding up all the other players in your tournament is less than ideal, so don't spend too much time asking players to repeat the stories you've already heard. Just get the information you think you can get, and then make the best ruling you can.