Halo Alpha
Halo Alpha

Decades of fighting against the increasingly adaptive Covenant has forced the Spartans to develop shorthand communications system for use against the Covenant. Many of these ideas are known and understood by the Spartans only, even as well-guarded secrets. These also sometimes make normal conversations with the Spartans impossible, as they can do a great deal inside their MJOLNIR armor that is indistinguishable from the outside. These signals include slight movements, cryptic statements, and radio communications.


Oly Oly Oxen Free[]

Main article: Oly Oly Oxen Free

"Oly Oly Oxen Free" is a simple six-note tune that SPARTAN-IIs can whistle as an all-clear signal or to make others aware of their presence or location. Virtually no non-Spartan except Dr. Halsey knows it, so they can use it with guarded impunity over the COM.[1][2]

Spartan "Smile"[]

Having grown up as soldiers, the Spartans kept their emotions to themselves, always controlling "bursts of emotion." The closest thing to an emotional symbol is the "Spartan Smile," used in place of a smile. The Smile consists of a quick swipe across one's own faceplate or a teammates with two fingers. The former way was usually used in place of the latter.[3]

Open COM[]

The Spartans signal to one another to open private COM frequencies by the flick of a finger. It is a move performed only in non-combat situations, when the Spartans can pay attention to each other's movement. This way they can communicate with one another without any unintended people hearing the conversation.[4][5]


Nonverbal signal used by Fred to countdown to the decompression of a captured Covenant ship's atmosphere in Ghosts of Onyx.  Consists of blinking the green, then amber, then red acknowledgement lights.


The Spartans will click a COM channel twice to get the attention of their teammates if they need assistance.[6] Recent improvements in Covenant sensor technology have made this gesture increasingly impractical, as Covenant will be made aware of a Spartan's location if that Spartan uses the COM in the presence of a Covenant vehicle.[7]


The Spartans sometimes console one another non verbally with a simple bump or gesture of the shoulder. They have become used to their Mjolnir Armor, so each move they make is deliberate. Hence, the gesture is easy to recognize and understand.[8]

"Trouble Ahead..."[]

A Spartan scout may signal that there is trouble ahead with a slight shake of the head from side to side.

"Stay Cool"[]

A short lateral cut with the hand across the chest or mouth area signals to stay calm.[9]

"Inspect Armor"[]

By making a circle in the air with one to two fingers to turn around, a Spartan signals that they want to visually inspect another Spartans armor. Even if the computer diagnostics report everything as fine, Spartans don't take chances with their armor or any other machinery and still visually inspect each other's armor.[10]

"Come Forward"[]

In combat, Spartans motion one another forward by flashing an index finger twice, sometimes two fingers are used for this gesture.


Spartans tell one another to wait by flashing an amber acknowledgment light twice on their HUDs.

"Fall back, Fall back!"[]

Spartans signal one another to fall back immediately by winking three red acknowledgment lights on their HUDs.

"Friendly Approaching..."[]

On the battlefield, verbal communication could risk giving away one's position. Therefore, Spartans inform allied positions that they are approaching by winking their acknowledgment lights green twice.


Slowly making a fist signals to tell a Spartan team to freeze.[11]



The Spartan-IIIs "welcome" one another by swiping two fingers over their faceplate. This is a smooth, silent way to say hello, and is a toned down version of the SPARTAN-II's "Spartan Smile."

"Unknown Ahead"[]

Spartans on patrol who spot something ahead that is not immediately discernible as ally or enemy will signify it to their teammates by making a hand signal with a thumb pressing into the palm and the other fingers inwardly curled.


This sign was only used once by Lucy in Ghosts of Onyx. This was signaled by holding up both palms, and making a down-and-up motion. It only had one recorded use in the books. However, this is the actual sign for heavy in the American Sign Language. Due to the post-traumatic vocal disarticulation Lucy suffers from the battle at Pegasi Delta, Lucy uses some form of ASL to communicate.


  1. Halo: First Strike, page 166
  2. Halo: The Fall of Reach
  3. Halo: First Strike, page 268
  4. Halo: First Strike page 3
  5. Halo: First Strike, page 120
  6. Halo: First Strike, page 16
  7. Halo: First Strike, page 314
  8. Halo: First Strike, page 8
  9. Halo: Ghosts of Onyx, page 205
  10. Halo: First Strike, page 299
  11. Halo: The Fall of Reach, page 206