If Fiora (4 might, no buffs) is targeted by both ticks of Falling Star after the opponent passes priority, and then En Garde is played in response to make Fiora 6 might with Deflect, does the opponent need to pay the Deflect cost?

Ruling: No, the opponent does not need to pay the Deflect cost because both triggers have already selected their targets before En Garde was played. Deflect only applies when targets are being selected, not after they've already been chosen.

Sequence:

• Falling Star is played and goes on the chain
• Priority passes and Falling Star resolves
• Falling Star creates two reflexive triggers that both immediately go onto the chain and select their targets (both targeting Fiora)
• Now priority passes again and you can react with En Garde
• Since targets were already selected before En Garde gave Deflect, no Deflect cost needs to be paid

Nuances:

• The optimal play would have been to play En Garde as a reaction to Falling Star going onto the chain (before it resolves), so that when the two reflexive triggers are created and select targets, they would have to pay the Deflect cost
• You cannot play En Garde between the first and second target being selected - both triggers go onto the chain simultaneously after Falling Star resolves with no priority passing in between
• Reflexive triggers are identified by specific wording: "do this X times:" or "then do this:" (with a colon)