Mortal Kombat 1

The Unstoppable achievement in Mortal Kombat 1 is one of the achievements related to the Invasion mode, which is a new mode that resembles a turn-based tabletop RPG. To unlock this achievement, you need to reach Invasions Level 10, which means you have to complete 10 Invasions missions. You can access the Invasion mode from the main menu, and you will see a map with different regions that are being invaded by other realms. You can choose to defend your realm or attack another one, and each mission will have different objectives and rewards. You can also encounter other players in this mode, and you can fight them or cooperate with them. You can earn Invasions XP by completing missions, fighting other players, and participating in mini-games. You can also unlock loot, such as gear, skins, and augments, by playing this mode. You can check your Invasions Level and progress from the Invasion menu. You will need to be online and connected to the WB network to play this mode and unlock the achievement.