The situation is this: My model shoots a target which is standing partially within a terrain zone, let's say a nimbus grenade, but there's a line of sight between them which doesn't pass through the zone. Is the zone applied? From the wiki I I've only found this: Equipment that requires LoF and is declared from, into or through a Poor Visibility Zone suffers a -6 MOD to the relevant Attribute in the required Roll. Consequently, any Skill, Special Skill or piece of Equipment whose LoF makes contact with a Poor Visibility Zone suffers the -6 MOD. That leaves it ambiguous as to whether the zone applies when a model's only partially within the zone and the line of fire isn't being drawn through the zone. Would the zone not apply? Would it apply only to one model (firing "from" or "into" the zone because one model's touching it)?
The answer is in the template weapons section. "Any trooper in base contact with a Template, or whose base or Silhouette Template is covered at least partially by a Template, is equally affected by the Template Weapon or Equipment." http://infinitythewiki.com/en/Template_Weapons_and_Equipment#Types_of_Template
Yes it's applied. Not just because of the template rules but because of the rules for who is affected by terrain. From http://wiki.infinitythegame.com/en/Special_Terrain_Rules Area of Effect of Special Terrain Zones The Area of Effect of a Special Terrain zone is the area in where its special effects are applied. Any trooper in base contact with a Special Terrain zone, or whose base or Silhouette Template is covered at least partially by Special Terrain zone, is equally affected by the Effects of the zone.