Going off your history. Vow: symbol reading and locating. Root: connecting light/darkness nodes from a starting point to an end point. Crota: pick up relic to charge a buff. When charged, someone else needs to take relic off them or they die. Buff is used to hold hove swords, walk through barriers, and activate hive tech. Salv edge: ping ponging a signal back and forth on plates to spawn darkness items so you can eventually close some nearby pillar. Go watch a vid. Seriously.

How so?