Which player's triggered abilities resolve first when a Showdown begins?

In a Showdown, the active player’s triggered abilities resolve first because the game's rules dictate that the active player's effects take priority in situations like this. This concept is grounded in the turn structure of most card games, where the active player—who is currently taking their turn—gets to resolve their actions and abilities before the non-active player can respond.

This prioritization is crucial for maintaining the flow of the game and ensuring that players can strategize based on their current position. Since the Showdown begins based on the active player's initiative and control of the game state, their triggered abilities occur before those of the non-active player. This structure allows the active player to create opportunities and influence the outcome of the Showdown more effectively.

The other options do not align with this rule. The non-active player does not have their abilities resolve first because that would disrupt the intended balance of the game. Abilities resolving simultaneously would create confusion and disrupt the turn order, which is clearly defined to enhance gameplay. Lastly, the idea that no triggered abilities occur during Showdowns contradicts the rules that provide specific instances where such abilities can trigger. Understanding this sequence is vital for strategic planning and decision-making in the game.