The Black Garden/Walkthrough
From Destinypedia, the Destiny wiki
This is the last mission of the base campaign. Your task is to enter the Black Garden on Mars and stop the advancing Darkness. You spawn into the mission in the Valley of the Kings, where you'll see a giant portal to your left. You'll want to enter that portal to advance to the next part of the mission. There are some enemies you'll have to kill, but it should be fairly easy if you can avoid the blasts from the Minotaurs. Once you enter the garden after killing the few Vex, you'll follow the arrow to the first area, where some Vex will spawn and attack you. After you clear this and about 3 more rooms, you should encounter a Darkness Zone, where you can see nearly the full scope of the Black Garden. You'll then be directed to a large room where you have to scan two Vex clusters with your Ghost to connect them and be able to advance into the final room. Once the large door opens and the enemies have been killed, you then enter into the very heart of the Black Garden, where you see many Vex Goblins praying. There are also three statues in the center of the area- the Eschaton Mind, the Imminent Mind and the Primeval Mind (One for present, future and past). The first mind only wakes up once every enemy has been killed. After you wake the first mind, it will spawn lots of enemies and you must pick them off and kill each of the three minds. Once all of the minds are dead, the mission ends and you fly back to the Tower for the final cutscene.