So it's clear to me that when you start your movement, you can move a partial troop, let's say you move 4 of 5 units and a Scarab. I have two movement points left. When I move again, can I split the unit again? Leaving 1 unit and taking the other three and the scorpion.
Basically, can I move a unit while dropping troops off as I go?
You can. But this will make your troop weaker and much more tempting target. Not to mention 1 unit troops, which you're leaving behind.
You can also leave behind one unit with a creature and still use creature's movement points for moving your main troop.
One of the threads on this subject: Leaving creature while moving -> movement bonus applies?
So does my opponent show me his card before I pick my two that I play or discard, or do they show me their card before I make any card choices at all? My thought was before I make ANY choices, but I know there have been a few questions about this card so I wanted to be sure.
Opponent discards one of his cards.
Opponent chooses and shows you (plays) his "battle" card.
You discard one of your cards.
You chooose and play your "battle" card.
Official ruling: Prescience