Where the Race Phase does not have a set turn order, can a player play a card that is not phase specific (as an example, Greek Fire) just after another player plays a dice to move forward into a square but before they move (in this example, causing them to take damage)? Or does an action need to fully resolve (placing a die, then resolving what it produces) before a Boost card can be played?
Greek Fire IS phase specific, as stated by the card: "Playable during the Venting Phase only"
None of the cards playable outside the Venting Phase involve player interaction. Hope that helps!
Keep rollin' sixes,