Assassinate 25 colonels.

In certain locations around Panau there will be colonels; there are 50 altogether but you only need to kill 25 for this trophy. As you wonder around Panau you may see what looks like a badge pop up that is black and white and has some white stars on it - this signals that you are near a colonel. There is also a name next to the badge so you know which colonel you are near.

The colonels are more advanced than the normal soldier, they have more health and a very unique body armour. This armour restricts you from shooting them normally and instead requires you to go for headshots or use an explosive. Also be careful when going for the colonels because they are also protected from other soldiers so you may also need to take care of these, otherwise you may die.

Some are located in bases, some are in villages/towns and can be on the floor or on rooftops. If you are struggling to find any of the colonels then please refer to the following thread, this was made courtesy of slaptarze at xbox360achievements.org and is used here with his permission.
Colonel Locations
If you need to know which colonels you still need to find then open up your PDA, press and scroll down to colonels. The ones ticked off have already been killed, the ones that havent still need to be assassinated.