[Ligma]

There's a check to see if you get agro from a beneficial spell

http://www.eqemulator.org/forums/showthread.php?t=39819

NPCs can fail a 'witness check' (Sony's term, mentioned in patch notes) in which case they will completely ignore a beneficial spell cast by a player which is in their hate list.

This means you can cast a heal on somebody tanking a NPC and have a chance to not get on the NPC's hate list at all. This is why healing is less effective than hitting NPCs for getting faction hits in groups/raids.

My data suggests that witness check rates are not affected by distance or angle to the target. Levels of the caster and target also seemingly make no difference, however I have not tested every possible combination of level disparity due to the difficulties involved. I did run some tests involving characters that were lower in level from the NPC, which produced the same success/fail rates, although the tank was still a higher level. (I had the casters usually casting on themselves however, not the tank)

The data does indicate that rates are not the same for every spell. Endure Fire for example was witnessed at a lower rate (about 40-45%) than most other spells I had tested-- those were around 50%. Minor Healing also resulted in the same lower witness rate as Endure Fire on a level 68 NPC casted by a level 65 character. I have not tested many spells due to the significant amount of time required to gather the data.

An old cleric thread from early 2004 has some clerics running tests, and they also came up with the 50% chance for heals to aggro, testing on low level NPCs: http://www.eqclerics.org/forums/show...t=17872&page=3 however their sample sizes are small.

See the pastebin link for my data.