He was said to show up as the main antagonist.
Supposedly EQG 5 will be about the Equestria Girls government noticing all the strange anomalies happening (just like Sci-light did at the end of EqG 2 and in EqG 3) along with the strange reports they’ve been getting and sends some young looking special agent named Ace Thruster in to infiltrate the high school to find out what’s going on.
He’s not alone, as he has a fellow agent named Coffee Klatch working with him and is his wingman.
Both are from the Bureau of Otherwordly Investigation (BOI).
BOI thinks that Equestria is evil and trying to take over the world by sending in magical creatures and using magic to corrupt people.
They want to destroy the portal or take the fight to Equestria.
Basically agents of the goverment dispached by the organization Bureau of Otherworldly Investigation to stop the menace of Equestrian magic.
There are no physical descriptions of them or their personalities. So many came up with their own as seen here.
Funny enough, some took one look at Ace’s name and assumed he’d be a waifu thief and a cowboy cop.
Kabayo drew his own interpretation along with the others put forward before in this.