The Sons of the Patriots (SOP) system is a way for teammates to connect together. To activate SOP, hit the "triangle" button when near allies to salute (when standing still) or do a quicker hand-gesture (when crouching or running). A large bubble will go out, and any ally it passes over will be linked to you. They will be marked as blinking, glowing silhouettes on the screen and as blinking triangles on your map.

SOP helps you keep track of your team - their locations (both map-based and on screen) and where they're looking. When an SOP-linked ally raises their weapon, you get a "laser pointer" showing where they're looking. The main purpose of this is that if you notice an ally firing, you can easily see where he's looking and if he's engaging an enemy (at which point you can help him out). Another purpose is so that when you are moving ahead, you can see if your allies are covering you from behind by the laser-sight that's going past you.

Another feature of SOP linkups is that various status effects are registered by the system. By this, I mean that if you have an ally, and that ally is killed, you will receive an icon indicating "death" and a laser pointing to his location (both direction and height). There are several kinds of icon matchups - death is represented by a skull and an alarm noise, knockout is represented by a star and a pinging noise before the alarm noise (as are all non-lethal notices), sleep is represented by a Z, a person reading a magazine is represented by a heart, and codec messages are denoted either with a blank circle (regular messages), an exclamation point ("Enemy spotted"), or a question mark ("I heard something/huh?") and a pinging noise.

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