Ruby

Rin didn't want to do this, she acknowledged that this was possibly the only way left short of putting effort into repairing the greater grail and using Illyasviel's last gift to access the root. Regardless that was still tempting when compared to this.

She and Sakura sat in the living room of the Matou mansion, Rin staring daggers at the chest they had pulled out of her leftover materials that were stashed here, Sakura looking curiously between her sister and the box to determine what she was so angry at.

Rin sighed with displeasure and stepped over to the chest, she knelt before the lock and pressed her hand against it. She sent a small jolt of power from her family crest to break the sealing spell that she had placed on the chest and slowly went to unlock the chest with a set of keys she had picked up from her supplies. Seconds passed slowly as she slowly unlocked the chest before finally Rin put the keys away.

"Sakura, stand back a few steps" Rin softly ordered, She didn't want to risk the item within the chest doing something stupid.

Slowly the chest was opened. When it stood open on it's own and wouldn't close if she let go, Rin took a deep breath and placed her hand into the chest, searching out the item she knew was there. It only took a few moments to find it, her fingers encountered the grip and Rin recoiled. After calming down for a moment she put on a pair of gloves she had prepared earlier and reached for the object again.

Sakura was curious of what in the chest was so important and would cause fear in Rin? It was something made by Kaleidoscope so it would likely use second magic in some way but apart from the jewel sword blueprints she had never heard of him giving out mystic codes to the Tohsaka family.

Rin slowly grabbed the object by the grip and slowly lifted it out of the chest, as she did she felt it trying to draw in magic power into itself. Rin knew that as long as she didn't put her blood on it, it couldn't wake up fully but she worried what might happen should it partially wake up on it's own.

Sakura looked at the wand in her sister's hand, she saw Rin hold it as if it was some evil tool. Briefly Sakura compared it to how she would likely hold a crest worm if forced too and with that thought she began worrying what exactly Rin was holding.

Rin placed the wand on a table and started casting as many binding spells as she knew, she didn't want this thing to run around on it's own again. When finally she was satisfied with the bindings she took of the gloves and used her dagger to prick her finger before touching the blood to the wand on the table.

A second past, Sakura was trying to choose whether to ask Rin about what she was doing when a shudder passed through the wand on the table and Sakura decided to stay quiet and see what was going on.

Finally Rin saw the slight struggling of the wand that means it was trying to move and her bindings restricted it. She forced a smile before speaking "Welcome back Ruby, I hope you are well" the second part was a very poor lie but pleasantries were a good way to start things.

Sakura was startled as a childish girl's voice emanated from the wand "[[Is that little Rin?]]", Rin forced herself to speak again "Yes it is Ruby, I have a job for you finally".

A laugh emanated from the wand as Rin slowly explained the problem (She left out things that the kaleidostick had no needs of knowing).

Finally the wand went silent as if considering the problem before asking "[[He has part of your crest Rin? I wonder what sort of boy could get you to trust them with that?]]" the tone of voice was teasing and Sakura looked away trying not to imagine when Shirou had been with Rin like that. Sakura didn't have to call on a specific memory as she wasn't in the house when that was going on, she had been having a mental breakdown that could have destroyed the world.

The wand spoke again a few dozen seconds later after teasing Rin about the other parts of the story that she hadn't been able to hide "[[As long as he bears your family crest I can find him, your plan (for once) is not awful!]]".

As Sakura sighed in relief Ruby stopped giggling for a moment "[[Is someone (kinder than Rin) back there, I'm afraid the binding spells on me currently make me blind.]]"

Rin looked annoyed before nodding to Sakura who cleared her throat and politely said "How do you do Ruby, I am Sakura... Tohsaka Sakura" The wand was silent for a few seconds before 'whispering' loud enough to carry throughout the room "[[Rin, I thought that your sister was sold of to the Makiri family?]]"

There was a moment of silence while Rin clumsily explained that as the Makiri family had died out apart from Sakura and thus they had nothing to teach her she had been graciously (To be fair they chatted once before agreeing) offered the chance to return to the Tohsaka family.

Ruby chuckled for a moment before asking Sakura to join Rin in directly talking to her. Ruby introduced herself using every dramatic title she could think of (To be fair she had maybe 2 or 3 titles, she made them sound dramatic) and Sakura listened calmly wondering why Rin was show scared of the kaleidostick.

Finally Rin released the bindings on Ruby so she could calculate the way to get to Shirou. As she was calculating Sakura turned to her sister and asked "Why were you so afraid of Zelretch's proposal, this is working fine". The words were not even out of her mouth before Ruby started swearing "[[You can't be serious Rin I had assumed you had decided to use me on your own (A wise choice as I am amazing) but now I hear that my devil of a creator told you to use me]]"

Rin looked sheepish and outraged at the same time as Ruby continued "[[I finished the calculation but now I think you don't deserve my power!]]" with that she flew over to Sakura and asked in a charming voice "[[Can you form a contract with me lady (Much better than Rin) Sakura?]]"

Apparently just touching a blood relative was enough for Ruby to form a bond with Sakura instead of Rin (A good reason why truly intelligent mystic codes are a horrible idea) and with a great flash of light Sakura disappeared. Ruby hummed to herself as Rin looked on devastated.

Ruby looked at her expression and giggled "[[I sent her to the dimension you two were looking for, I did what I was told to do by my master and now you can't contract me until you apologise]]"

Rin looked at the wand and tried to decide between more wood for her fire or to use Ruby as a battery after destroying any sense of mind still left in that piece of firewood

After the bright flash of light Sakura found herself somewhere different, instead of being in her own town she appeared to be in the middle of a desert. She had no supplies, no spare water and was on a sandy plane with the sun beating down from overhead.

She thought she now understood why Rin disliked the Kaleidostick.

End of Interlude

Anyway, so Ruby is out and has already made Rin's life hell.

In addition Sakura is now in creation, the south specifically (Though anyone who knows Exalted could have said that the moment I wrote desert)

Timeline wise, Sakura entered creation between chapter 1 and 2

I tried to do the brackets that Ruby has in Fate/hollow ataraxia but the signs used in HA couldn't be used in apparently

Also as alluded to in the text Rin gave part of her family crest to Shirou (as per UBW) to combat Dark Sakura, Another major difference between normal Heaven's feel and the backstory here was that the team going after the greater grail was much bigger (including Saber, Rider and a crippled Berserker). The thing basically went a lot better than in pure Heaven's Feel but they never made the jewel sword (They didn't think they had the time).