Crossfire is a free-to-play military-themed online shooter game developed by NeoGate and published by G4Box. It is very reminiscent to the original Counter Strike 1.6 game both in gameplay, and the graphics style, which is similar, but in much higher resolution than that game. System requirements are very low compared to today's standards, so the average home PC can most likely play this one too.
The game has 4 main game modes. These are Team Deathmatch, Search and Destroy, Elimination, and the Crossfire-unique Ghost Mode, in which one team only has knives but they are ghosts who are invisible while standing and translucent while on the move. Each of these game modes have specifically tailored maps, about 5-10 each. There are many smaller, less important game modes too, such as Zombie mode, Free for All, Escape mode and more.16 main weapons and fewer pistol types, and 5 types of characters are available. The game is played between 2 and 16 players on community-run servers.
If you liked the original Counter-Strike 1.6, but can't afford to buy it or any newer versions, or simply dislike them - this game is for you, as its gunplay and movements are very similar to that game.