Netherrealm's Injustice 2 boasts several modes, one of which is an arcade mode that can be played with any character to fight a series of opponents before going up against the game's main villain, Brainiac. Defeating the green-hued villain unlocks a specific ending for each of character used, and they're varying shades of wild! For example, Bane will conquer Gotham, only to grow bored with his conquest, while Joker decides to spread his terrifying form of humor over the captives aboard Brainiac's ship.
However, the best endings by far are given to the DLC characters transferring to the Injustice 2 reality from other universes. Currently, there are three non-DC universe characters on the game's roster: Cryo-ninja Sub-Zero and Thunder god Raiden from Netherrealm's Mortal Kombat, and Dark Horse's Hellboy. The endings for these characters are so good, choosing them to kick Brainiac's butt during the final battle will make you wish you could see their future adventures.
Let's start off with Sub-Zero, since he was the first character of the three to join. While fighting Kotal Khan, a character from the Kombatverse, Sub-Zero wound up in the Injustice world by magical means right around the time Brainiac had begun his attack on Earth. Never one to let such injustices stand, the ninja froze Brainiac solid, thereby defeating him. As payback for the help, Batman and the rest of the Justice League did everything they could to return Sub-Zero home, while the ninja occupied his time by training newcomer League members Supergirl, Firestorm and Blue Beetle. Just when the League thinks they've got it, they actually don't, and wind up opening a portal to the Phantom Zone, the inter-dimensional prison that houses several villains, including Superman as of late. Feeling honor bound and remorseful for being stuck on this Earth in the first place, Sub-Zero joins the Justice League to fight Superman and his followers. Yeah, that's pretty awesome... and it only gets better from there.
Raiden's induction into the Injustice world is fairly similar: He began having visions of Brainiac's collecting, visions that would soon destroy the barriers placed across the multiverse and destroy existence altogether. After defeating Brainiac, Raiden learned from the dying Doctor Fate that DC's pesky Lords of Order were the cause of Raiden's visions. Due to their efforts to obliterate Chaos, the multiverse would return to a complete state of Order. Not exactly rooting for multiversal genocide, Raiden joins up with the Justice League Dark, a collection of sorcerers and magicians -- the lineup includes Constantine, Etrigan, Swamp Thing, Deadman and Zatanna -- to fight the Lords of Order and bring a pure balance to the universe.
Hellboy's ending is less bombastic, but still pretty awesome. He arrived in this world after Brainiac started making hungry eyes at Big Red as the latest addition to his collection. After all, it's not every day you see a red demon with a giant fist smoking a cigar and petting kitty cats. Naturally, Hellboy's response was to punch Brainiac's head clean off his body. He stuck around for a while, nabbing criminals with Batman, though he quickly found that this world just wasn't to his liking. Unlike Raiden and Sub-Zero, though, he did manage to make it back to his universe, but things there felt comparatively small. Thus, he leaves his lifelong home of the B.P.R.D. and packs up for Africa, where he manages to find the space he was craving... and no shortage of monsters to fight.
If there's a downside to any of this, it's that the adventures of these guest characters won't be followed up on. The endings are all non-canon, so we'll never get to see what a Justice League with an ice ninja or God of Thunder would actually be like, nor will we see Hellboy hang out with Batman to punch Two-Face in the faces. With the Ninja Turtles coming to Injustice 2 in a few months, their ending is sure to be equally ridiculous as well, and we can't wait to see it.
UPDATE: An earlier version of this article indicated that Hellboy creator Mike Mignola provided artwork for the character's storyline. This was incorrect, and the story has been updated accordingly.