Can an opposing player stop Traveling Merchant's move ability from triggering (through death or bounce) before it resolves and allows the turn player to play Flame Chompers from the graveyard?

Ruling: You cannot stop Traveling Merchant or Flame Chomper abilities from triggering unless you remove Merchant before it moves or remove Chompers from hand without discarding them. Once triggered, these abilities go onto a chain and you can react to them, but currently there are no cards that can stop them from resolving.

Sequence:

• Traveling Merchant moves, triggering its "When I move" ability
• Flame Chomper gets discarded, triggering its "When you discard me" ability
• Both triggers go onto a chain
• Opposing player can react to these triggers on the chain
• Triggers resolve unless prevented by a card effect

Nuances:

• These are triggered abilities, not passive abilities
• The only way to prevent triggering is to remove the source before the trigger condition occurs (remove Merchant before it moves, or remove Chompers from hand without discarding)
• In theory abilities can be stopped from resolving, but no cards currently exist that do this