first:
You first question I didn't understand, maybe you have to be more clear.
second:
If you mean the electric/spasm animation you do this by using "
ent_fire survivor_death_model Shock" in the console.
I made a plugin related to that:
[L4D2] Survivors Dead Bodies Spasm
third:
This entity is a created with a
TE_SetupBeamRingPoint.
Here is an example:
beacon.sp
You can test by yourself with "
!beacon @me"
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