There weren't too many "big" questions asked at the pre-release. Here's a few as I remember them:

Q: If a (blue) creature with trample is blocked by a creature that later is given protection from (blue), what happens with the trample damage?

A: Just like normal, you must assign enough damage to "kill" the blocking creature. The rest can be assigned to the opponent (and the damage to the creature will be prevented, of course).

Q: Can I "do something" between the time my opponent pays for a spell and pays the Kicker cost?

A: No, paying the kicker cost (and deciding to do so) is done as part of announcing the spell and paying appropriate costs.

Q: If I attempt to move into my attack phase and my opponent does NOT respond (and I subsequently attack with no creatures), can I declare an attack with creatures later in the turn?

A: No, by declaring an attempt to move into the attack phase without the opponent responding, you are declaring a null attack (phase moves from declaration of attackers straight to the end of combat step) and you can't declare another attack this turn.

Q: What happens if a round ends with one player having 1 win and the second game is still going?

A: If the second game doesn't end in the 5 extra turns, the player with 1 win will win the match.

Q: If I cast Yawgmoth's Agenda, does that count as my one spell for that turn?

A: YES. This has recently been changed by Dan Gray on the judge's listing to reverse the FAQ's ruling. Note that I ruled on this question at the prerelease and used the FAQ answer (not thinking the FAQ would be wrong).

Thanks to the David Taylor at the Philadelphia Invasion Prerelease for keeping track of the questions they were asked.

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