mentor/supervisor/guide: someone who cares about you

An individual, typically a role-model, coach/ facilitator, or expert, who has accepted some increased responsibility for another's development, including helping that person achieve mastery level in Middle Skills or Big Skills. They may perform tasks including after action reviews, and help understand Processes.

In a Sim

Within a sim, a mentor is a partially or completely pre-scripted character who provides instruction (see in-game tips/directions) and exposition, through alerts and cut scenes, but unlike a coach, does not break the fourth wall.

Guide. In FarCry, while in the dark belly of the best, the hero is contacted through a cell phone by the guide, who provides constant framing and advice.

In a traditional hero's journey, the mentor/guide is a critical enabler of the hero, giving both advice and also exotic items. Often, the mentor either dies before they end of the journey or betrays the hero.

Author's note: In corporate sponsored educational simulation, the role of the guide is often the benign and helpful supervisor.