1. Obsidian
I'm 100% sure that he will never be a character in Injustice, but I think that his powers have great potential in a fighting game. He would be a swift rushdown character with insane cross-up potential.
- TRAIT - Shadow Clones: Create shadow clones that mimic attacks (Morrigan's "Astral Vision" in MvC)
- Shadow Form: Intangibility and Flight (Ability to pass through opponents and projectiles pass through him)
- Shadow Constructs and Darkness Manipulation (Could do some crazy vision stuff)
2. Black Canary
I think Black Canary could be an awesome "defensive rushdown" type of character. She could have a fighting style that's similar to Lili from Tekken who mixes up opponents with delayed inputs, and She-Hulk in MvC who uses Command Runs and Wall Jumps to get in close safely.
- Several parry techniques that open the opponent to extended combos; could include a wall bounce throw and some other neat stuff
- SUPER - Canary Cry: Martial arts sequence into her canary cry that stuns the opponent for extended combos
- TRAIT - Wall Jump and Command Run (She-Hulk and Strider Hiryu in MvC; Lili's dodge spin in Tekken)
3. Brainiac
I honestly don't know
too much about Brainiac, but my boyfriend wants him in the game, so I'm listing him here. xD I vaguely know of his powers, but from what I know, his moveset could turn him into a crazy "defensive zoner."
- Force Field: Blocks enemies and projectiles from passing; really amplifies his zoning capabilities. Could also have an enhanced version that surrounds him, similar to Phoenix's in MvC3, but perhaps explodes and causes a wall bounce when an opponent approaches.
- Telekinetic Traps: Traps that move the opponent in different directions. He could have several command grabs that have great synergy with these traps and his trait.
- TRAIT - Machine Alien Army: Brainiac could summon machine aliens that grab stun the opponent, cause ground bounces, or push opponents away. These would be great as combo extenders or combo finishers. He could also set turrets that have strong push back, giving him scary cross-up potential when used in conjunction with his traps, summons, and command grabs.
4. Zatanna
Zatanna could be a zoner that heavily focuses on mix ups and deception. She has a lot of potential to have a unique moveset.
- Illusions and Polymorphing: If anyone's familiar with Mu-12 from Blazblue, I think Zatanna could similarly fire spells from different screen angles using illusions as well. And of course, polymorphing abilities could be used in many ways.
- Card Tricks: Could implement a meter gamble or meter stealing mechanic
- TRAIT - Reverse Spell: Inverts player controls; potentially irritating, but I admit it'd be pretty awesome. :X This is implemented in several ways in Playstation All-Stars Battle Royale and MODOK uses this in MvC3. It would really strengthen her mix up capabilities.