If I move Travelling Merchant to a battlefield occupied by my opponent's unit, then chain Flash to return my Merchant to base before the showdown starts, does a showdown occur at all?

Ruling: No showdown occurs. When Flash resolves and returns your Merchant to base, the battlefield is no longer contested because control is re-established (the opponent's unit still controls it, and no opposing unit is present). The staged combat is removed, and your Merchant triggers twice (once for moving to the battlefield, once for returning to base).

Sequence:

• Move Merchant to occupied battlefield, triggering its ability and placing it on the chain
• Game state becomes neutral closed (chain is present), combat is staged but does not begin yet
• Cast Flash targeting Merchant while holding priority, adding it to the chain
• Flash resolves, moving Merchant back to base and triggering its ability again
• Contested status is removed because control is re-established (no contesting unit present)
• Staged combat is removed
• Both Merchant triggers resolve (discard and draw twice)

Nuances:

• The key is that combat cannot begin during a neutral closed game state (when the chain is active)
• Contested status is removed when the contesting unit leaves, allowing control to be re-established
• This scenario differs from when the controlling player's unit is removed while contested, which creates an unresolvable bug in the current rules