When Urza enters the battlefield, it and Deadeye Navigator's soulbond ability trigger.
Resolve the Deadeye Navigator trigger, repairing it and Urza.
Resolve the Urza trigger, creating two 0/0 Construct artifact creature tokens.
Activate Urza's first ability twice by tapping the Constructs, adding .
Repeat.
This brilliant sequence turns Urza, Lord High Artificer into a self-sustaining engine by utilizing Deadeye Navigator's soulbond ability to repeatedly blink him back onto the battlefield. Each time Urza re-enters, Doubling Season steps in to double his token-creation trigger, flooding your board with twice as many Construct artifact creature tokens as normal. You can then immediately tap those newly minted Constructs for mana using Urza's built-in ability to pay the blink cost, allowing you to loop the process indefinitely for an endless army of tapped tokens.