Does a showdown start automatically when a unit moves to an occupied battlefield, or can you move multiple units separately before declaring the showdown?

Ruling: When a unit moves to a battlefield, a showdown begins automatically. However, you can move any number of your units together to the same destination with one standard move action.

Sequence:

• Multiple units can be moved simultaneously to the same battlefield as part of a single move action
• Units moving together can come from different locations (base, other battlefields)
• All units arrive together before the showdown begins

Nuances:

• Units must all be going to the same destination
• Each individual move must be otherwise legal
• This applies regardless of where units are moving from (e.g., two units from base and one from another battlefield with ganking can all move together)