Wolfspartan90 made a very good point that I would like to make a small edit to. He said he saw (I have as well) new players just shooting the Scorch Cannons. When using them you can HOLD THE SHOOT BUTTON to increase damage. They will eventually auto-explode, dealing massive damage. A strategy against these Spider Tanks (as we Destiny 1 veterans know them) is to use TWO FULLY CHARGED SHOTS to take down a leg. When the "brain" is exposed, (especially the first time because the tank remains like this longest on the first time) just shoot it as fast as possible, except few the last shot. HOLD THE LAST SHOT. This ensures maximum damage. If you are trying to trigger heroic mode, DO NOT KILL THE TANK AS FAST AS POSSIBLE. Upon destroying a leg, the tank will drop three arc charges. Even as most new players know, DISPENSE THE ARC CHARGES INTO THE CONSOLES GUARDING THE CANNONS. To trigger heroic, you must expose all six Scorch Cannons (by destroying two legs without all of the cannons yet). I hope this had been informative and helps at least one person out there.