Rob van Zyl
1. Do I have to play all three cards?
2. Do I turn them over all at once or one at a time?
As stated on card, they are played in any order, so all three cards are drawn.
3. What happens if I get a reroll or other dice altering power when the last roll is already done?
Any rerolls or dice altering effects granted by cards, are in addition to the initial two rerolls. Therefore, these dice effects would be resolved.