If my opponent controls 2 walkers and I bolt them, can I redirect 2 to walker A and 1 to walker B?
No. Your choices are 3 to your opponent, 3 to planeswalker A, or 3 to planeswalker B. You have to redirect the damage as a single lump sum.
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If my opponent controls 2 walkers and I bolt them, can I redirect 2 to walker A and 1 to walker B?
No. Your choices are 3 to your opponent, 3 to planeswalker A, or 3 to planeswalker B. You have to redirect the damage as a single lump sum.
Can I respond to my spell after my opponent passes priority, before it resolves? Ie. Cast lightning bolt, pass priority, opp doesn't respond, and I want to reverberate it before it resolves.
No.
If you pass priority, then your opponent passes priority, your spell will then resolve.
If you want to cast Reverberate, you either have to hold priority and cast it immediately or just hope that your opponent will respond to it.
Opponent opens with leyline of the void. I enchant myself with wheel of sun and moon. What happens to a card that goes to my graveyard? Yay replacement effects!
Both effects are trying to change where the card goes instead of going into your graveyard, so as the affected player you get to choose which effect to apply. You can put the cards you want back on the bottom of your library and other cards into exile.