Elden Ring Shadow of the Erdtree continues the tradition of the base game, consisting of extremely challenging quest lines with very few hints. Players are almost certain to encounter certain items and non-playable characters that will leave them completely perplexed. One such example is the proper use of the consumables Grace Rainbow and Dark Rainbow. Here's what they are used for.
The Grace Rainbow and Dark Rainbow are unique consumables that are quite difficult to find.
Note. Do not use the Grace Rainbow and Dark Rainbow! Their quantity is limited, and losing one of them may block access to a certain element.
Technically, you can use the Grace Rainbow to activate the effects of your Great Rune (just as you can with rune arcs, for example). But you need to save the Grace Rainbow to use it in one of two side quests, as giving the Grace Rainbow to other characters will reward you with special items.
The Grace Rainbow is located in the Shadow Keep in Scadu Altus. You are most likely to find it after defeating the boss Messmer the Impaler on your way to the next area, the Ancient Ruins of Rauh, but you can also find it at any time once you have access to the Shadow Keep's Storehouse and the Storehouse, First Floor site of grace.
Here is the exact location of the Grace Rainbow on the map screen:
To find the Grace Rainbow, head west from the Storehouse, First Floor site of grace into the first corridor you see on the left. You will have to deal with enemies if you want to pick up the Rune Arc on the corpse; otherwise, you can proceed down the corridor until you reach the elevator.
Take the elevator down and go into the first corridor on the right. An enemy will rush at you from the door on the left, so be on guard as you pass through it. You can also take the new Ash of War «Wall of Sparks» from the room where the enemy came from.
You will reach a staircase leading down into another room with more enemies. If you want to deal with them one by one, slowly lead them back up the stairs to make them easier to handle. Be careful as you approach them.
Pass through the room into the next area, and you will find more miniature jar monsters. They are somewhat easier to handle, but be cautious as there are many sleeping enemies here that can easily sneak up on you.
However, before you venture deeper into the Shadow Keep, stay in this room and face east. Behind you, you will notice another living jar monster, and if you go to the end of the room, you will find the Grace Rainbow at an altar in the darkness.
In Shadow of the Erdtree, you can find three Dark Rainbow items. Luckily, you will only need two of them to complete certain side quests. So, if you are having trouble with the tree spirit near the sunken chapel, don't worry. You can safely leave it alone and come back to it later.
Inside the Fort of Reprimand in Scadu Altus.
The Fort of Reprimand is located in the southern corner of Scadu Altus. You can reach it by heading south from the Moorth Ruins or through the Gravesite Plain, using a hidden route to bypass Castle Ensis. Here is the exact location of the Fort of Reprimand on the map screen:
In the courtyard at the main entrance of the fort, you will need to descend into the cesspit using the square opening on the north side of the courtyard:
There you will find several corpses with items, but to get the Dark Rainbow, you need to defeat the Horned Warrior who rushes at you from around the corner with two greatswords.
At the statue before you reach the Scadutree Base.
The second Dark Rainbow can be found in the Shadow Keep in Scadu Altus, right before you reach the Scadutree Base where you fight the Scadutree Avatar. However, you will need to drain the church area on the east side of the Shadow Keep before you can access this item, as it is only available after the water level has been lowered. Here is the exact location of the Dark Rainbow on the map:
From the Sunken Chapel site of grace, head west and turn right when you exit the chapel building. Sneak past the tree spirit slumbering in the round plaza near the chapel and enter the church on the left (the one with all the exploding fire monsters inside).
Run to the end, but before you reach the alcove with the large statue, turn right and go through the passage to the north.
Go through the large doors under the balcony in the next room and take the elevator down to the Scadutree Base. When you reach the bottom, activate the Tree-Worship Passage site of grace and cross the wooden bridge. On the other side, you will find another chapel with a large statue at the end. The Dark Rainbow will be there.
Defeat the Ulcerated Tree Spirit in the drained church area of the Shadow Keep.
The third Dark Rainbow can be found by defeating the tree spirit in the drained church area of the Shadow Keep. It is actually very close to where you found the second Dark Rainbow mentioned above.
In this area, there are two tree spirits, and the Dark Rainbow is your reward for defeating the one located north of the Church District (not the one inside the round columns near the church). Here is its exact location on the map screen:
Start again from the Sunken Chapel site of grace, but this time head east from the chapel, following along the back wall around the round plaza to your left. On your way up the steps, you will encounter crabs.
Ignore the tower with the elevator inside and instead descend on the left side of the tower to the north, between the two large church buildings.
As you approach, the tree spirit will emerge from the ground and leave you an item after you defeat it.
As mentioned above, the Grace Rainbow can be used exactly like a Rune Arc to activate any Great Rune you have. But you can get the most out of this rare item. Save it for two side quests in Shadow of the Erdtree:
When you progress far enough in each of these characters' questlines, you will have the opportunity to gift them either the Grace Rainbow or the Dark Rainbow. Depending on which one you give them, you will receive different rewards.
It is important to note that while you can only collect one Grace Rainbow item, you can still use it for both questlines. As a result, you do not need to worry about which questline you complete first, as you will still have the opportunity to give the Grace Rainbow to the second character once you get there.
Here is what you can receive from each character depending on which Rainbow you give them:
It is important here to choose the desired reward from each character, as you can only give them a Rainbow once. It is impossible to receive both rewards in one playthrough, so choose wisely!