Does Wielder of Water get +2 might when moving into an empty battlefield, and can it be targeted by Gust?

Ruling: Wielder of Water does not get +2 might when moving into an empty battlefield because it is a showdown, not a combat, so there are no attacker/defender designations. Therefore, it can be targeted by Gust.

Nuances:

• Wielder of Water's ability is a passive "while I'm defending alone" effect, not a "when I defend" trigger, so you cannot react to it with Gust during combat
• If player 2 moves units to a battlefield where Wielder of Water is already present, combat starts when the battlefield becomes contested, attacker and defender are assigned, and Wielder of Water has 4 might before there's any opportunity to use Gust (unless player 2's movement opened a chain from a move-triggered ability)