If you have a Hare Apparent in your hand, cast it by paying 1. If not, activate Emiel by paying 3, blinking a Hare Apparent.
When Hare Apparent enters the battlefield, it and Dual Nature's first ability trigger.
Resolve the Dual Nature trigger, creating a token copy of Hare Apparent.
When the Hare Apparent token enters the battlefield, it triggers, creating a number of 1/1 Rabbit creature tokens equal to the amount of other creatures you control named Hare Apparent.
Resolve the Hare Apparent trigger from step 2, creating a number of 1/1 Rabbit creature tokens equal to the amount of other creatures you control named Hare Apparent.
Activate Ashnod's Altar twice by sacrificing two Rabbits, adding CCCC.
Activate Emiel by paying 3, blinking a nontoken Hare Apparent.
Hare Apparent, Dual Nature's first ability and Dual Nature's second ability trigger.
Resolve the first Dual Nature trigger, creating a token copy of Hare Apparent.