how do u make low gravity in SIngle PLayer
if you mean for mapping, the same way you would for HM. pick a brush, the floor, a wall, the ceiling, and then hit N. in the entity box, enter a key of gravity, and a value of 1 to 800. default is 800, half gravity is 400.
if you mean in the game as you play, I can't help you.
If you want to change gravity in game open the console and type:
I dont know if it works for ef2
changing the gravity is good, but using it with high knockback is better.
To change the knockback you type: g_knockback X (default is 1000. To get photon burst knockback, add a 0. To get knocked across the room, add three 0's.)
To change your speed type: g_speed(or mabye it's g_runspeed or something to that effect.)(150 is normal, 300 is rabbit, 700 is roadrunner, >1000 bullet. Be careful with these.)
If you put a negitive # for gravity, if you jump up and get stuck on the roof.
These work with sp and mp. Have fun!