Does Whirlwind trigger Deflect?

Ruling: Whirlwind does not trigger Deflect because it is not a targeted spell. The units are chosen by players after the spell is cast, not targeted when the spell is played.

Sequence:

• Whirlwind's cost is paid when the spell is cast
• After the spell resolves, players choose units
• Since the choice happens after casting (not during targeting), Deflect's additional cost does not apply

Nuances:

• When card effects refer to "choose" in contexts like Deflect, it actually means "target"
• Rule 352.10.e specifies that objects chosen in whole or in part by other players are not targets
• Deflect is an additional cost paid when playing a spell, so if the choice isn't made when finalizing the spell, Deflect doesn't apply
• Targeting is the only way to choose a unit when finalizing a spell