Coke boosts stamina/damage capacity and makes them believe they are invulnerable (like the Columbian drug lord in Hitman 47).
Acid makes people permanently hyper-paranoid.
Amphetamine boosts alerness and agression (to a higher degree than the "go pills" given to USAF pilots).
Marijuana enhances damage capacity/reduction, without the feelings of invulnerability. Prevents body from going into shock due to injury, thus worsening any bleeding injuries.
Just some thoughts.
EDIT: Now someone checking my browsing history will have a field day

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