CQC and knives are difficult weapons to master, but once you have done so - and if you know how to use them - they are powerful weapons indeed. With the CQC skill equipped, you can get enemies into chokeholds, and also defend better against enemy chokeholds. A chokehold's stamina damage rate is based on the attacker's CQC vs the defender's CQC. The attacker's CQC being better means that the attacker will deplete the enemy's stamina quickly. The defender's CQC being better means that the defender is more likely to escape (by spinning the left analog stick). 1 level of CQC is also required for two other skills - Knife level 3's throat slitting ability, and the Scanner ability (with Scanning Plugs).

The Knife skill grants you the ability to move around while using the knife, which grants you more mobility than the usual "stand still and wave the knife around" that unskilled soldiers have. When using the knife, try to catch someone with the Stun ability (R2) and then slice their unconscious body up with the blade. Level 3 Knife paired with Level 1 CQC grants you the ability to insta-kill an enemy caught with CQC, at the expensive of not being able to fit any other skills.

When using melee attacks, try to hide and wait for someone to pass you. Run up behind them and catch them from behind, either with a chokehold or a stun attack. Stealth is key here; use shadows and the Cardboard Box to blend in and escape notice, then attack. Try to pick off single enemies traveling alone, who are less likely to have someone who can shoot you. If there is someone in the way, you can use CQC to put their ally between you and them - if they hit the ally, the SOP Friendly Fire system will disable their gun for a few seconds, enough for you to knock out / kill your captive or shoot the enemy with a pistol.

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