The best way to describe Lucky Races is to start by referencing the game Mario Kart or Crash Team Racing where players race around a track, pick up items, and use those items on themselves or other players in order to finish the race first.
Now take the real-time aspect of racing and stretch it out into phases like this:
All players have a window of time to choose up to two actions
Once that window closes the Play Phase is over.
Each Play Phase is followed by a Processing phase, where those actions are processed by the Game on the Blockchain.
The game updates state for everyone simultaneously at the end of the Processing Phase and begins a new Play Phase for player actions.