How can i find Spartan Ghosts in Halo 3?

[spartan117]

hey guys,
i read in Halopedia that there are ghosts in Halo 2 & Halo 3's multiplayer who appear as Spartans, who dont have a walking animations, so they just look like their sliding on the ground...
i heard that they appear only spawn after you overloaded a map, and i accually overloaded many maps!
but i never saw any ghosts..
how can i find them easily?
is there a special way?
thanks!

 

[Tahir]

Go to the building on the left and ull see the spartan on the roght u dont shoot or hell go away