Graduate
From Halopedia, the Halo wiki
Graduate
Spartan Graduate is a Halo 3 multiplayer achievement. It is awarded when the player completes the requirements for basic training on Xbox Live and reaches the rank of 
Private. To reach this rank, you must just play at least once in multiplayer. It is represented by a gray plate with two crossed Battle Rifles.
Following the shutdown of Xbox 360 Halo online services in December 2021, this achievement will no longer be attainable.[1]
Rewards
Unlocking this achievement rewards the player with the following;
- 10
- ODST multiplayer armor permutation.
Additionally, players also lose access to the Basic Training playlist upon unlocking this achievement.
Sources
