Child of the Moon

Your lunar gift becomes much more powerful when the moon is full.
  Benefit: Choose either Climb, Stealth, or Swim. You gain a +1 trait bonus on checks made with the chosen skill. On dates during and after the first quarter of a lunar phase but before end of the last quarter (the half of the lunar cycle where the moon is fuller), this bonus increases to +2. During the full moon, this bonus increases to +4.