Awhile back, significant changes were made to monster AI in the way they interact with players, hirelings, and their respective summons with respect threat and agro. Enemy monster AI was changed to put more emphasis on attacking healing classes and caster classes (such as clerics and sorcerers) as opposed to rushing towards the first thing they happened to see. However, the AI was also changed in a way that made monsters to head straight for any summoned creature, whether it be from a spell or from as a pet.
In many ways, players use this ability as a minor way to control monster aggro. It amazes me how this occurs across all level ranges and still surprises me today. For instance, in the above picture I had Stoorage’s hireling cleric summon his spider in the Tangleroot Explorer area. In almost all occasions, the mobs (primarily the trogs, wolves, and wargs) just made a bee-line for the summoned spider, completely ignoring the Stoorage (the larger threat) and barely putting any notice to the hireling cleric.
This is also interesting to watch with the snow elemental, that can be summoned forth from the snow elemental gem that can be created during the Risia Ice Game event. I was running Erdrique with another guildie through Redwillow and we just watched as the snow elemental just grabbed aggro even though Erdrique was cleaving away and my guildie was getting huge sneak attack numbers.
In either case, it worked for me. The only downside to this, is that in many instances the summons will grab so much aggro that they will get overwhelmed and get killed relatively quickly. So, many times this aggro management is short lived, but it is interesting to watch how the mobs are so drawn to our summons. 🙂