Yi Jing, Oracle of the Moon

Zhèn-Gěn, Thunder-Mountain
    

  When Zhèn becomes Gěn, there is thunder in the mountains, long far rumbling. Mountain tames Thunder's impulsiveness, but together their voices reach far. When those two forces support you, your actions become powerful and focused. You often act behind the scenes, but that does not diminish their impact. You consider influences that others find not important, too small or vague, and that adds subtlety to your strategy.

This is the short answer - click for the complete one (with 'your' helpers).

  About the 3 lines of the trigrams and the helpers:
  Each line, active or at rest, summons one of the 8 trigrams as a Helper. For an activated line: telling you what you need - or about a problem area or something to avoid.
  For a stationary line: this is what you already have or do or what you don't need. Often we just need a reminder of our abilities. Or it could be what you wish or fear - but will not happen.
  Active lines are the helpers to change things, they listen to intentions, which can come from you, surroundings, or fate. Stationary helpers are part of the core meaning, they are your soul talking, but they also see the impossibilities or what is lacking at the moment. They reinforce the overall power of a reading.