DJ Demon J
Banned
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This game took Counter-Strike to the next level, but was never noticed due to poor marketing by EA and BF1942's release shortly afterwards.
Not only did you buy weapons, armor and accessories, but also weapon upgrades. Not hitting your targets with your P90? Slap on a laser sight. Not enough ammo for your chaingun? Attach the super-size ammo holder. Some weapons had multiple ammo/accuary/secondary add-ons in addition to their standard primary/secondary fire modes.
The 6 character classes (Recon, Heavy Gunner, Commando, Medic, Sniper, Demoman) were distinct and the gameplay encouraged the use of all classes (Demoman opens up faster routes to objectives, Recon can place enemies' positions on his teams' radar, etc). Add incredible sound effects for the weapons and great level design and you have a winner. Sad to see this game go ignored yet people still play Dust 2 over and over.
Recently I found this for sale, full box and manual in mint condition, for $5 (!!!) at EB. I highly encourage FPS/Counter-Strike fans to get this.