Nick is a detective from Coast City. He recently transferred to Gotham City and works alongside Commissioner James Gordon. He has only been in Gotham for a short period of time and has already had a shocking number of arrests and convictions. They call him "St. Nick" because he is the best Christmas present the Commissioner has ever gotten. He is kind of like Batgirl's Commissioner Gordon and has somewhat of a romantic interest in Barbara Gordon
He was created by Bryan Q. Miller in 2010
Crime doesn't Clay
In Gotham's financial district, Detective Nick Gage acts as the police negotiator while talking to Mr. Griswald, the crazed husband who is held up in his van. Gage tries to talk Griswald down and have him come out of the van. Unfortunately, Gage's task force comes under unsuspecting fire and the SWAT team is called in to retaliate. As the SWAT team approaches the van, Griswald throws a petrol can that bursts causing everything and everyone to go up in flames. Gage was in safe distance from the explosion and spots Griswald running from the van.
Gage still tries to convince Griswald in turning himself in but Griswald refuses to acknowledge Gage as they make their way to the roof of a building. The pursuit ends when Griswald has no adjacent roof top to jump to and Gage holds him at gunpoint. However, Griswald seems unfazed by the gun as he causes himself to explode into a mountain of clay. The explosion sends Gage flying off the building but as he fell, Stephanie swoops down to save Gage. The duo glide down to a nearby alleyway until Proxy informs Batgirl by via comm link that Clayface has made his way to Gotham's Bank & Trust.
After a huge scuffle with Clayface, Steph and Karlo end up outside the bank because of an explosion. When the smoke clears, Stephanie awakes unharmed since Clayface's body absorbed the impact of the explosion but she also discovers that there is another version of herself. Gage's task force doesn't know who to apprehend until one of the Batgirls orders Det. Gage to shoot the other Batgirl. Fortunately, the real Batgirl simply gave Gage the go ahead to fire at her. Gage soon realizes that only Clayface would ask him to shoot somebody. Clayface is exposed and Stephanie uses a batarang filled with liquid nitrogen to freeze Clayface. Clayface is sent back to Arkham Asylum while Det. Gage reveals the real reason why Clayface wanted to get inside the bank's vault.
The Slipstream Lesson
During the Slipstream robberies, Gage arrives at Branch 19 of the Gotham Bank and Trust where a bizarre crime scene has just been committed. Stephanie eventually appears at the scene as Batgirl. Gage informs Batgirl that this is the third unusual bank robbery this week. The only damage to the bank was at the front door and the vault door. Gage and Batgirl also review the security feed from the bank’s closed circuit television. They soon recognize a blurry image that set off the pressure censor alarms in the bank.
They both figure Slipstream, a servant of the Reaper gang, intentionally set off the alarms to mock the decisive duo after their last encounter with the shadowy speedster. The security feed also reveals that Slipstream only stole a couple thousands of dollars and left millions more behind. Steph is curious as to why Gage is making this particular case a personal matter. She asks Gage if this case has anything to do with the murder of his ex-partner's son Nelson Flitwick. Gage just brushes off Steph's suspicions and leaves the crime scene. After Steph apprehended Slipstream, she hands Slipstream over to Det. Gage but Gage as well as Steph notice that Slipstream doesn't seem at all concerned that he is going to Blackgate.