When Player A controls a battlefield, Player B moves Traveling Merchant to that battlefield (triggering contested status), and Player A plays Flash in response to remove their own unit, what type of showdown occurs?

Ruling: This is a known rules gap that the current rules do not properly handle. The two reasonable interpretations are either a combat showdown occurs (skipping damage assignment since no opposing units are present) or the defender loses control and a non-combat showdown begins.

Nuances:

• The contested status locks control of the battlefield, preventing the normal loss of control when a player has no units present
• The rules don't clearly specify what happens when all defending units are removed in response to a move trigger before the move resolves
• Kelly (a Riot representative) indicated the rules would likely be tweaked so the answer is "combat showdown," though they personally find "lose control + noncombat showdown" more intuitive
• A potential fix being considered is moving the control lock to occur during a showdown/combat rather than when contested status is applied