Campaign Event

The Campaign Event is one of the types of Events that you can choose to perform during your turn's Event Phase.

At the start of a Campaign Event, the turn player must choose one of their inactive creature or monument zones to conquer (represented by putting a marker onto it). If they have already conquered all their 6 non-artifact zones, they must draw a card instead. This must be done immediately when starting the Campaign Event.

As a bonus for having chosen this event, every face-up creature the player controls gets the March Action added to their Action Pool.

Then the player can proceed to perform Actions with their face-up cards as part of any Event Phase.

This is certainly the first event a player will choose in a duel, because at the very first turn they won't have any creature available to benefit from the Battle Event.