If I move Traveling Merchant from base to battlefield, and opponent responds with Fight or Flight (moving it back to base), does the 'When I move' ability trigger once or twice?

Ruling: Traveling Merchant's ability triggers twice - once from the initial move to battlefield and once from Fight or Flight moving it back to base. You will discard 1 and draw 1 twice total.

Sequence:

• Traveling Merchant moves from base to battlefield (Standard Move)
• Trigger #1 goes on chain: "When I move, discard 1, then draw 1"
• Opponent plays Fight or Flight as a Reaction
• Fight or Flight resolves, moving Merchant from battlefield back to base
• Trigger #2 goes on chain: "When I move, discard 1, then draw 1"
• Trigger #2 resolves: discard 1, draw 1
• Trigger #1 resolves: discard 1, draw 1

Nuances:

• Both movements qualify as Moves because any permanent changing position from one space on the board to another is a Move (unless it's a corrective Recall)
• The ability has no location-based targeting requirement, so it doesn't matter where the Merchant ends up
• Any effect that moves Traveling Merchant will trigger the ability, whether it's a Standard Move, Ride the Wind, Fight or Flight, or any other movement effect