1. Opening the app- Tap the Injustice: Gods Among Us icon on your mobile device to open up the game.
2. Main menu- At the main menu, you can play against computer teams in the missions mode, against other players in Online Battle mode, get new cards in the Shop, look over your Collection, or check out your Settings and options. Tap Collection.
3. Collection menu- In the Collection menu, you can look at your characters, upgrade them, look at support cards, and look at gear cards. Tap Gear Cards.
4. Gear Cards- Gear Cards can be fused to a specific character or shattered to produce Shards. Shards are necessary to fuse, and the color and amount will depend on the Gear Card you are trying to fuse. In addition to Shards, fusing also requires Credits, which are obtained by fighting and winning either in regular play or PVP. Once you have all required items, tap Fuse and select the character to Fuse with.