Mister Miracle might well be the most durable of the myriad heroes and heroines created by Jack Kirby for the DC "Fourth World". As seen above the original concepts were a wee bit different than final product, especially the notion that Mister Miracle might rely on a gun.
Here we see the ultimate design as worn by Thaddeus Brown, the original Mister Miracle.
Scott Free steps in to save the day and in doing so shows that he has the bravery and spunk to be more than a bystander.
Later he shows that he as skills, talents, and equipment which make him a most remarkable replacement for the original. He takes the role when Brown is killed and makes it his own.
Scott himself, is on Earth hiding from Darksied's terrifying Granny Goodness who took charge of him when he, Highfather's son, was traded for Orion to make a peace many years before. When Scott escapes Apokolips he gives Darkseid an excuse to reignite the conflict, which this time brings the New Gods to Earth.