The Buddy is a single player AI in the mobile version of SAS: Zombie Assault 3 that provides cover fire for the player. Its initial Rank is Private (Rank I). Their movement is quite frantic and will not survive long unless the player offers to protect their Buddy. Both the player and the Buddy earn their own XP and rank up. Additionally, the player can even decide what their Buddy's name should be. The appearance of the Buddy is the same as the player's model except being tan colored and the Buddy's gun is always copper colored.
- Having the Buddy activated will offer additional help to the player when dealing with overwhelming groups of zombies.
- The Buddy can also distract other zombies so the player can be given enough time to reload or switch to another weapon.
- Pathfinding is not always perfect; for example, if the player's AI Buddy is in another room while the player is facing in front of their Buddy on the other side of a barricade, the AI will instead hug against the wall which will later result in the partner's death if not corrected soon.
- Buddies will frequently spend money on ammo; it's best to deactivate the Buddy if the player wants to avoid losing some of their already earned money. However, a Buddy can be equipped with a pistol to solve this, as pistols come with unlimited ammo. Additionally, the player can choose whether or not to let their Buddy use premium ammo.
- The AI has a few flaws. When you die (in single-player), rather than the buddy avoiding the zombies (while waiting for you to respawn), it will usually charge through the zombies, which will cause instant death to him before you can even revive yourself, thus resulting in a Game Over.
- The image of the Buddy in the Main Menu is actually a cropped photo taken from the Airbase map's loading screen.
- On Challenges, player will not be able to play with the Buddy, but he will still earn XP if Buddy is activated.