In Horizon Zero Dawn (HZD) you need all possible optional allies to join the defense of Meridian if you want the bronze trophy “All allies joined”.
What to do:
Play up until the main quest “The Looming Shadow”. This is main quest #21 and the final mission of the game (can check progress in notebook stats).
Before doing the first objective of The Looming Shadow, go and do the following 11 side quests:
- Traitor’s Bounty > Queen’s Gambit
- A Moments Peace
- A Daughter’s Vengeance
- Sun and Shadow
- Honor the Fallen
- Sunstone Rock
- Hunting For the Lodge > Hunter’s Blind > Deadliest Game > Redmaw
If any quests are unavailable it’s because you haven’t progressed far enough in the story. They will all be available by the time you reach “The Looming Shadow”. If you run into a quest earlier feel free to complete it.
Once all side quests are done, go do “The Looming Shadow” main quest. You get the objective to go to bed before the final battle. This unlocks the trophy during a cutscene when Aloy is sleeping.
After completing the last mission it will put you back before the Looming Shadow quest and it can be replayed as many times as you want. So if you missed a side quest it’s no problem. You can still do those after the final mission and then replay it.
Names of All Allies:
You can go talk to all of them before the final battle. You’ll get two optional objectives to visit both defense sites (Spire and Ridge). The allies can be found there.
*Dialogue choices do not affect this trophy. Personally, I always chose heart, so that’s what I tested and confirmed to be working. The developers have since confirmed that dialogue choices do not affect the trophy.
*Killing Nil in side quest “Cause for Concern” does not impact the trophy. He doesn’t count as an ally. The trophy unlocked for me despite killing Nil. The characters that you can kill don’t count as allies.