NetherRealm Studios has unveiled a new exciting gameplay trailer for its upcoming superhero brawler Injustice 2 showing off Robin in action for the first time. Revealed by the developer during a Twitch livestream, the almost 2 minute-long trailer shows Boy Wonder himself taking on other confirmed characters in Injustice 2's still-growing roster including Batman and Deadshot.

"I can't forgive the deaths," Batman says in the trailer.

"I'm your only son, old man," Robin responds, to which Batman retorts: "Death was my son, too.

Injustice 2 continues the story of 2013's Gods Among Us which is set in an alternate DC Universe. After The Joker tricks Superman into killing a pregnant Lois Lane, a series of events result in the Man of Steel becoming a fierce, troubled dictator.

In Injustice 2, Batman and his team of super-powered heroes and villains try to restore society whilst battling another group that is working to reinstate Superman's Regime.

Creative director Ed Boon also announced that the codes for the Injustice 2 online beta, which he teased last week, are currently going out. The first wave of beta invites have already been sent out with more to follow, he said.

In the beta, which is available to players in North America, fans can play as one of four characters: Batman, Superman, Supergirl and Atrocitus. Other characters may also be added over the course of the one month-long, multiplayer beta which will feature 1v1 battles, the developer noted.

During the livestream, Boon also teased that Injustice 2 will feature some rather obscure characters in its line-up as well. He suggested that the developer could release some third-party characters as DLC for the game as well, noting that they were quite popular in Mortal Kombat X.

He also noted that Injustice 2 will feature the largest roster ever for a NetherRealm title, both in terms of on-disc and DLC characters. He emphasized that the new super-powered fighter is taking steps to avoid letting players pay to win, adding that gear will not be sold for money in the new game.

Boon also said the most ambitious aspect of Injustice 2 is its story mode, describing it as the "ultimate Justice League interactive, cinematic experience."

"In the midst of the chaos, a new threat appears that will put Earth's existence at risk," the developer previously teased. "Players can play from the biggest DC roster ever offered in a fighting game, from classic fan favourites such as Batman, Superman, Supergirl and Aquaman, to astonishing new villains like Atrocitus and Gorilla Grodd. Battles will take place across arenas that have evolved in scale and span across iconic locations such as Metropolis, Gotham City and Atlantis."

So far, Injustice 2's roster will include mainstays such as Superman, Batman, Wonder Woman, Supergirl, Flash and Aquaman. It will also feature a diverse line-up of villains including Atrocitus (which Boon revealed is his favourite new character), Gorilla Grodd, Harley Quinn and Deadshot.

Last week, NetherRealm released a dark new story trailer that confirmed supervillain Brainiac will be the sequel's main antagonist and showed other baddies including Bane and Poison Ivy joining the line-up.

Injustice 2 is slated to launch on 16 May for PS4 and Xbox One.