Ok Common [spoiler]a guardians purpose is to stop the darkness from destroying the traveler[/spoiler] Uncommon [spoiler]we kill zydron gate lord for access to the black garden[/spoiler] Rare [spoiler]Qqdrons detainment shield does damage over time[/spoiler] Legendary [spoiler]the purpose of the oracles is to determine what is and isn't real so the vex can mold the perfect future[/spoiler] Exotic [spoiler]the nine send xur to release skolas from his prison so he could warn the queen that oryx is coming because he saw the arrival of oryx in a vision[/spoiler]