Now you can do high jumps in this game :) No fall damage. Also contains versions for two episodes, Synergy, Left 4 Dead, Left 4 Dead 2, Half-Life, Half-Life Source, Counter-Strike Source, Counter-Strike GO, Half-Life 2 Deathmatch, Portal and Portal 2. Added flying mod for Half-Life 2 and Synergy, which also works in Half-Life Source, Half-Life 2 Deathmatch and Counter-Strike Source. By unknown reason flying mod add some strange bugs in game world, if you not want meet any bugs, then play only with jump addition