Post: #9

@SpellEffect
if (<src.isplayer>)
src.sysmessage you can't attack players
return 1
endif

Check in wiki the tiggers
http://wiki.sphere.torfo.org/index.php/@SpellEffect

Like:
The following object references are explicitly available for this trigger:
Name Description
ARGO The item used to cast the spell (e.g. a wand or scroll).
I The character or item being hit by the spell.
SRC The character responsible for the spell.

@spelleffect fire when you recive any spell, so SRC is who cast the spell, then you check if isplayer and prevent damage with return 1