Can players cast action spells multiple times throughout a showdown, or only at the start before any reactions are played?

Ruling: Players can cast action spells multiple times throughout a showdown, not just at the start. Using a reaction does not prevent you from casting action spells later in the same showdown.

Sequence:

• Player receives focus
• Player may cast an action spell
• Players may cast reactions back and forth (chain resolves)
• Focus passes to other player
• That player may also cast an action spell
• This continues until both players pass focus in order without starting a chain

Nuances:

• Players cannot play multiple actions in a single chain, but can play multiple actions across different chains within the same showdown
• The showdown only ends when both players pass focus consecutively without starting a new chain