Can Yasuo, Unforgiven's Legend Ability be activated during a showdown to move a unit from a battlefield to base?

Ruling: No, Yasuo's ability cannot be activated during a showdown. His ability has default timing restrictions and can only be used on your turn, outside a showdown, with nothing on the chain.

Sequence:

• Must be your turn
• Must be outside a showdown
• Must have nothing on the chain